It may be +3 and +2a that it doesn't like
Viewing post in Beltalowda (English Version) comments
You’re right. I’d tested the game on emulators with the 128K and +2 models, but not with the +2A and +3. It’s true that the first part fails using those models, but the second part doesn't. It’s not something I can fix because the process of creating the .TAP file is automated using 'DAAD Ready'.
I've just reported the bug to the developer, and they've told me he'll look into it.
This only happens in Part I; I've just played through the whole of Part II using a +2A ROM and finished it in its entirety.
I’ll add a note to the game’s page.
Thank you very much for your comment and for reporting this bug.
Best regards!