Blergh, Simon 2 is crap no matter what version.
I've never had the full Simon but I've got a CD32 coverCD with a demo on it. It used to play fine on my a1200 (remember to install nonvolatile.library, and possibly some others). Don't think I've ever tried it on the a4k.
The final version may be different, though. Some of the posts suggests something regarding the cd.device, so it may be. Back then the demo was used with an IDE drive.
Sincerely,
-Kenneth Straarup.