System Extensions or 'Create Your Killer GS/OS Environment!'

Posted by Alex Lee on 22 March 2011 | 70 Comments

Tags: Apple IIGS, System Extensions, NDAs, CDAs, CDEVs, INITs, Finder Extras, GS/OS, GSOS, System Add-ons, Enhancing, System 3, System 4, System 5, System 6

Using system extensions is much like a juggling or balancing act - while there are many great ways to enhance GS/OS, you're limited by how much RAM you have, slowdowns, how well each extension gets along with each other and if they were specifically written for the version of the GS operating system you want to use.


System Folder


Back in the day, I 'only' had 2.25 meg of RAM in my ROM01 IIGS and I thought it was plenty. I played around with quite a few extensions, but ultimately, I liked a lean System 6, as it seemed more stable, saved precious drive space on my 40 meg Vulcan, and left enough memory to play the most demanding game and run the most resource intensive creative apps.

Now of course, emulators make it much easier to play around with your ultimate personal System 6 install, as speed and drive space are many, many more times faster and capacious than back in the '80s and '90s. To enhance GS/OS, open your system folder and copy the individual relevant files from the System Add-ons volume into their respective folders according to what type of system extension they are. I'm aware that you can simply copy onto the 'System' folder from the root directory in System 6.0.1 and it will automatically move the file into its correct folder, however when done once, it doesn't seem to work again, and the System folder loses its icon and turns yellow. Is this a known bug or a conflict extension?


Loaded System 6.0.1


Anyways, some observations I've made spending hours cataloguing and playing around with all these system add-ons in the hope of creating a definitive archive. It seems writing system extensions was just as perilous then as it is today: you could spend a lot of time developing an INIT, NDA, CDA, CDEV, etc. to extend GS/OS's capability just to have it made redundant when Apple decides to include it in the next version of the operating system. Although not included in this collection, SignatureGS is probably the best example of CDEVs that were made almost totally redundant in System 6, however they're still useful for System 5. DinkyLaunch by Richard Bennett allowed you to choose another launch program upon boot-up, which was superseded by the 'Set Start' CDEV in System 6.

It's also made me realise that finding the right combination of system extensions greatly enhances the abilities of your IIGS - I've been surprised and delighted by a lot of NDAs, CDEVs (what the hell does CDEV stand for?!) and Finder Extras, having missed them the first time around back in the IIGS' heyday.

Some of my favourites:


Ninja Force's DeskPlay for MOD Playback


André Horstman's Hermes/ShadowWrite for text viewing & editing


NDAs: Rolf Braun's Sound It and Mega Box (which between them will play most common sound and music formats from within the Finder or any other program) and DeskMaker (for specifying an image for your desktop) Ninja Force's DeskPlay for MOD playback, André Horstman's Hermes/Shadow Write for text reading and editing, Bret Victor's Mighty Units (for conversion) and Watcha Press? (for finding those accented characters).


Digital Exodus' DOCVu v2 for monitoring the Ensoniq's activity 

FTA's ZIP CDA for controlling your ZIPGSX in style



CDAs: Nathan Mates' Game Hacker (for when I'm lazy playing games), Digital Exodus' DOCVu v2 and the FTA's Zip CDA (for controlling a ZipGSX in style).



Nathan Mates' KillDaWhoosh for a nice speed up 

Nathan Mates' Flying Toasters Screen Saver conversion from After Dark



CDEVs: Nathan Mates' KillDaWhoosh (Kills the whoosh sounds and the animation for opening and closing windows - a real speed-up) and Small Extras (removing dividers between the list of Finder Extras and greatly saving space). Twilight II (the ultimate IIGS screen saver, which you'll find some new modules within this archive). I'd like AutoMenus v3 more if there was an option to allow a single and unsustained mouse click to pull down a menu rather than the menu opening as soon as you place the cursor over it! SuperClock is still my menu bar time keeper favourite.


Jupiter Systems Finder View - easy viewing images within the Finder


Finder Extras: Chris Vavruska's Finder Flipper (cycles between Windows with option-tab), Jupiter Systems' Finder View 3.0 (for opening nearly all graphics formats within the Finder).


Bret Victor's SlixTop (or Shadybar and Bender combined)


INITs: Nathan Mates' GUPP (Fixes lingering bugs in System 6.0.1) Bret Victor's Shady Bar and Bender (beautifies the menu bar and adds a shadow - I don't like how SlixTop makes the Menu Bar disappear though), and SlixLaunch (does a good job of mimicking OS X when opening an app) Sheppy's Tsukue v2.0.1 (for removing the switch to the text screen for non-System 6 apps) Snakebyte's Quiet Disk (prevents GS/OS from searching the slow and loud 5.25" drives), II Not Disturb (makes that menu bar clock fly), Sys Icons (displays much more decorative small icons in file dialogues), IR (for loading all system extensions on the fly, although some require them to be in their proper System folder locations).

What are your favourites and why? A few extensions have the same or similar abilities - why is one better over another? Add your thoughts to the comments field at the end of the article.

As mentioned before, it can be frustrating getting all system extensions to work so here's a few tips to make things a little easier with your expectations of maintaining a stable GS/OS: any system add-on that has all UPPERCASE filenames is most likely to have been written pre-system 5 and MAY exhibit problems when running from System 5 or higher. CDEVs were introduced with System 5, so you can't use them with System 4 or lower. Likewise, Finder Extras can only be used with System 6. Some add-ons may have trouble working under emulation - one such culprit was WinFlate, otherwise useful to minimise windows, but seems to make the emulated GS/OS environment within Sweet 16 not respond to mouse clicks.

Also, read the documentation included before installing anything. The docs will usually provide helpful tips, cautions and recommendations as to what version of GS/OS to use.


Bill Tudor's INITMaster Finder Extra to control all your extensions


You will likely run into extension conflicts at some point, which can happen when two or more extensions are trying to tap into the same resources of GS/OS, which will most likely result in the system failing during boot-up or weird behaviour and crashes afterwards. The most straight forward way of getting around this is holding down the shift key whilst rebooting, 'Get Info' on the troublesome extension (most likely the last one you installed) and click the 'Inactive' checkbox, then reboot normally. You can also use Bill Tudor's Finder Extra INITMaster to create different sets of extensions.

This archive will be revised if submissions are made, especially in regards to version tracking. Where ever possible I've always included the very latest version of any system extension, in the hope that it offers the most features as well as bug and conflict fixes. Let me know if you can provide a newer version of anything found within this archive, or indeed sometimes suggesting running an older version of something is better (Taifun Boot is the one example: version 1.8 found on Ninja Force's site doesn't seem to work at all). If you know I'm missing any public domain and shareware INITs, NDAs, CDA, CDEVs, Finder Extras, Launchers, icons, icon editors, font utilities, please let me know and where possible provide a full archive including documentation.

Much, MUCH thanks to all who came before me in collecting IIGS system tidbits - Jim Maricondo for the Golden Orchard/Grail archive, Brutal Deluxe for the DeluxeWare CD-ROM, the German AUGE newsletters, A2 Central Newsletters and anyone who had anything to do with the Ground and archives... and thanks to Greg Wildman for keeping mirrors of them.

Note that no GS+, SoftDisk GS or commercial system extensions have been included with this 32meg ProDOS image (there are MANY even more useful extensions amongst these collections). GS+ and Softdisk GS is still available for purchase at Syndicomm. I have made an exception for Bret Victor's work however, as he freely distributes it via his site.


 System Add-ons (13 meg)


Some commercial system add-ons, such as Six Pack, Signature and Beagle Brothers Desk Accessories, have been reclassified freeware but haven't been included in this archive for distinction between free/shareware and commercial software. Many of Bill Tudor's works were originally shareware but then updated for Six Pack's commercial release. Other commercial software that is now 'abandonware' i.e. no-one has a current license to sell, such as DeskPak, The Manager, TransProg III and Kangaroo, can still be downloaded separately as part of the broader archive of 'What is the Apple IIGS?'

Speaking of which, does anybody have version 1.5 of the Manager, Transprog III and Kangaroo in English? I'm thinking of resource editing the French versions to replace the French language for English if no-one has these archives. You can remain safely anonymous if you wish to contribute.

Oh, by the way, can anyone help with a very specific, useless and purely cosmetic INIT I *think* I remember using back in the mid 90s? I don't know if my memory's getting confused with the 'Aaron' extension for Mac OS 7.5 that would give your Mac the appearance of Mac OS 8 or not, but the extension I'm thinking of was create a spinning rectangle effect when opening and closing windows, instead of the usual un-spinning rectangle. Completely useless, but cool :-)

UPDATE: Mitch Spector's sent in his system extension collection which I've merged with this online archive. Additions include:

NDAs: Backgammon by Bill Tudor, QuickView by Dave Goetsch, Smiley Clock by ?, DeskTop Color v2 by Earl Gehr, Write it v2 update by CK Haun, freeware versions of Bill Tudor's CPU and Memory Use, Calculator by Tony Morton, Solitaire update to v1.0.6 by Bill Tudor.

CDAs: SHRCapture CDA by ?, Setup Imagewriter II CDA v2 by Bill Ruff, BASIC Errors by John Link, Arkanoid II Ultra Cheat by Ian Schmidt.

CDevs: Alert Sound by ?, INITMaster CDev (with full docs).

INITS: OmniScreen by ?, Title Pic by George B. Zamrov.

UPDATE 2: The archive now includes the Penworks NDA (for using a Kurta tablet), Brutal Deluxe PicViewer (lean, mean Finder Extra for viewing images in Finder, if only it would allow scrolling of images larger than 320x200!) and finally the recently re-released NiftySpell, which allows you to spell check in ANY desktop based program that runs under System 6.0.1. Ewen Wannop's done a great job updating this useful, but memory hungry, NDA. Check out Ewen's internet suite of desktop based apps for use with Marinetti v3.0b3 here.

UPDATE 3: After browsing through the British GS Users Club disks that Antoine Vignau has tirelessly turned into disk images, I have added the following to the 32 meg System Addons archive:

Tools: Tool 27 patch (Anyone know what this fixes?)


Calculator CDA by Terry Morris
STS Screen Saver CDA by Dale T Taylor
Screen Print by Jason Simmons
PlayCD b1 CDA by Aaron Pulver
Bye CDA by Terry Morris
Tearbar CDA by David Empson (now includes docs)

Finder Extra

Finder Flipper Finder Extra v1.0.1 by Chris Vavruska (Updated - hopefully fixes the bug that displays an error message every time you quit back to the Finder)


Password v2.0 CDevs by Brian D Wells


Scrap Master NDA by Dave Huang
Calendar NDA v1.2 by Greg Engelkemeir
JumboDesk v2.12 NDA by Jason Simmons (update from v 2.0)



This is easily the biggest update to the System Add-ons 32 meg volume. Apart from the new additions listed below, some duplicates have been removed, others put into more suitable categories.

Most notably, added software from Aaron Pulver — there's some very cool stuff here! Firstly, there's the NetTime CDev. This nifty control panel will enable you to sync to a time server (if you've got an Uthernet or LANCGS ethernet card and Marinetti installed), which helps allay the problem of incorrect time on your IIGS if your Battery RAM (BRAM) is dead (short of you having to manually update the time).

Another gem is Aaron's Address Book NDA. This little beauty includes cellular/mobile phone and email fields, something no other address book NDA does on the IIGS.

What's better still is that I recently got in touch with Aaron to ask for permission to include these system add-ons (along with Bisquit INIT, Freek NDA, Second Sight Toggle CDA) for Aaron was happy and also alluded that he's returning to IIGS programming to improve these system extras - hopefully to enable NetTime to be automatic on start-up (which in league with other BRAM system extensions, would negate the need for replacing your IIGS' BRAM!) and getting Address Book v1.0 final. Look forward to those updates!

And there's lots of miscellaneous new additions:

Finder Extras (FExts)

v1.0.1 updates to Chris Vavruksa's Finder Extras: CD Remember (a cool utility that remembers open Finder windows from write protected volumes (like CDs) when you return to the Finder after checking out an app, as well as Finder Refresher (redraws Finder windows) and Work Sets (which allows you to record a bunch of folders to open in the Finder at once).

rPacker Finder Extension by Brian D. Wells. An interesting Finder extension that saves drive space (and possibly load times) by deleting empty or placeholder resources. Back up your data (as the docs say) and give it a go - it might enhance the performance of System 6 on your IIGS. It doesn't seem to work with Sweet 16 however - using the same System 6 install I put rPacker on, it works fine with ActiveGS, but crashes the system on Sweet 16. When it works, I managed to save 62k of data running it through my System 6 install with shareware and freeware games. Not bad. Although I only scrounged 2.5k from the Action games volume.

Also from Brian is Fix Finder Windows. It's a patch that apparently fixes the ‘About', ‘Help' and ‘Preferences' windows and dialogue, although I can't fathom exactly what the problem is. I'll be trying this one time patch out regardless. Perhaps GUPP (the Grand Unified Patch by Nathan Mates) fixes the problem? It's included for completeness and is in the Patches folder.

Teach Reader Finder Extra by Jupiter Systems/Chris Trimble has been updated to v1.01, including several bug fixes.

Newer version (v2.0) of DiskOpen Finder Extra by Greg Betzel.

rBundle Banger FExt by Clayburn W. Juniel III. In the spirit of improving resources, rBundle Banger helps sort which filetypes are linked to what application you want opening them.


AZERTY NDA by Huibert Aalbars - for AZERTY keyboards, obviously, but not sure if it's needed for System 5 and up.

BRAM Detect NDA by ?, complete with source code.

A time waster NDA - Bugs by ?

RAMDisk Manager Demo NDA - only a demo, but purports to speed up RAM disk 3 times faster.

Minehunt NDA game by Nathan Mates.

Accessory Chooser by Alberto Paglino is yet another NDA to load other desk accessories.


AE RAMKeeper CDA - should provide useful utilities for those with these cards.

Switch Control Panel CDA by Tim Grams. Not sure what this does, but for use with the IIGS control panel and ProDOS 8 apps.

Nexus by Tony Morales - adds commands to NiftyList.

There's a CDA that unmounts Appleshare volumes. No docs included.

BASIC Errors CDA by John Link

CDA Term by Guy T Rice now includes all docs and source.


TWGS Reporter by John Link, another CDEV that provides info on your TranswarpGS, which I haven't been able to test without access to a TWGS. It may only work with System 5.0.2 as well. Can't imagine it would hurt too much if you gave it a go with System 6.0.1.

Font Editing:

Newer version of Font Edit (v2.01) with docs. and Font Scan v0.5.

Newer version of Font Doctor (now v1.0b11 over v1.0b9)


SF Fix - an init that fixes a bug specifically with System 5.0.4 and prefix #8 when returning from ProDOS 8 programs - never encountered this bug myself.

Le Fix - an init that fixes potential crashes caused by programs that incorrectly setup the line edit toolset incorrectly, apparently TML Systems' demos are the main offender.

Nicon patch by Jeff Dickson allows you to decide if startup icons for CDevs and Finder Extras appear at boot time. Useful for limiting the number of icons appearing when System 6 boots.


Ultra Blanker v2.06 by Robert S Claney is now included, but v2.0 is still included, as that still allows it to be run from System 5.0.4.

OnHold INIT by James Stanford that replaces the usual wristwatch waiting cursor with a spinning beachball (which is actually the last thing I'd like see whilst emulating a IIGS under OS X!).

Some new random Icons:

Mean 18

And even a couple of new finds for shareware/freeware games:

Let it Ride Texas Hold-em Poker game by Thad T. Taylor (a bit rough around the edges, but enjoy)

Battleship by Chad Faragher and Jim Gauld (I remember liking this back in the day, but it doesn't seem to let you quit!)

These new additions are actually on the  Sports & Unreleased Games (~13.9 meg) as there's no more space on the  System 6.0.1 Hard Drive Image (~13.3meg) volume!

As always, Antoine Vignau is to thank for a lot of this stuff (especially from his recently re-released DeluxeWare CD-ROM). I hate that guy. He's the nicest guy and the most amazingly talented programmer and cracker you could ever hope to get encouragement and aid from! ;-)


Even after all this time and existing software, there are still some system extensions I'd like to see on the IIGS.

1) AutoMenus, but configurable so you need a single click to pull down menus (currently, existing AutoMenus versions simply reveal the pull down menu if you mouse over them). With a click, this would mirror the convenience of Windows and OS X.

2) I'd love to see a Finder Extra that simply added the ability to restart the IIGS, changing the boot scan slot to 5 or 6. This is a feature that was included in MouseDesk, as well as Instant Access, and it's a great way to quickly start up that DOSless demo or game without having to manually change settings in the control panel. Good for real 3.5" drives, emulated ones, or with the CFFA 3000!

3) There's probably a third one, but now I can't remember it. Anyone else have any ideas as to what they'd like to see enhanced in System 6.0.1?


Anyone got a copy of Fontasm v2.x in English?