Aged Code Studio

I am beginning to suspect that the culprit is ACAtune or the aca1221 hardware.

This also crossed my mind. Can you check it without ACAtune?
When I did the tests on the ACA card, I certainly didn't have ACAtune.

If I boot without Acatune I won't get the fast mem and cpu boost tho.

Tried without but then I get the suspend/reboot crash window.

So I did a normal boot and tried again to turn of music, both with lha extracted and lzx and it crashes as soon as I try to turn off music!

I have 330 000 bytes free of chip mem.

This is really super weird. I've never heard of such incompatibility so far.

Try with this config (replace yours). It has the music and SFX disabled.

Same. Crashes in Paris after a while of interaction.

Please, use the online installer to download the latest version, and see if anything changes.

ADF-version installed via WinUAE onto the CF-card (the amiga does not have access to the internet).
Put it back into the A1200.
Booted the game.
Added my username 'Per' as always.
Game loads as normal.
Get into Paris.
Klick "skip Paris intro" text thing.
Game crashes to a black screen and nothing happens.
I do CTRL+A+A and wow, green screen with strange music then it tries to boot and it gets black, and then digital noise sound. CTRL+A+A again and it wont boot into workbench, it is stuck in this loop of the strange sounds.
Power off and on and it boots as normal.

So installer was even worse this - is - strange!

Definitely! I'm running out of ideas. But I have one more suggestion. If you are willing to try, I can send you a pure OS3.1 with only the necessary files to load the game. It's one of the systems I use for a very long time to test the game. I'll send you a PM with the link.