I already checked all pins with an oscilloscope. Continuity is good. Signals seem to be on all pins except for 1,2,4 and 6 if I remember correctly. Again, I'm not sure what to expect on these lines.

As for schematics, yes I have them, I even did post them on post #12 of this thread if you want to take a look.

I tried with an emulator to get familiar on how the Apple IIgs boots/works/behaves. It's definitely different from the real machine I got.

I'll work on the rom again and double check everything. I might order another ROM to test.

Thank you.

Pitou!