I tried cloning that good working iMac drive over to other older Mac a bit earlier this morning. I ran into problems that I did not expect, like the cloning software not liking the older non-extended format of the old drives. I thought this would turn out to be a bigger project than I wanted.
Not one to be discouraged, I decided to try comparing the system files on both of my original Bondi Blue iMacs, as the game files where the same ( I also found out that one iMac is a B model, while the other is an A). While some system files were newer on the Mac that was getting the ‘out of memory’ error when trying to use the Quake ‘mouse settings’, there were other files that were there too but not on the other iMac. Most of these extra files seemed pretty simple, and you would think that they would not affect Quake (like auto-time setting and such). I decided to match both systems as much as I could anyway, deactivating those few extra and seemingly trouble-free files.
Well, after making the changes and rebooting – and much to my delight – Quake now works on the model A Bondi iMac without getting the error when going into ‘mouse settings’!
Happy, happy, joy, joy!
Now all I need to do is get that to work with around 5+ other iMacs…. 
(But, sleep for now, it is very late – or early – depending on how you look at it).
More to come… (testing the LAN – hopefully much later today).