I've recreated the bug and I'll try a patch tomorrow. In the meantime it should work in the caprice32 core on Retroarch
Viewing post in Bubble Ghost (Amstrad CPC 6128) comments
With Caprice32 works fine !!!
https://github.com/ColinPitrat/caprice32
I haven't managed to get past the third screen; I don't know if there's something special I need to do—the bubble always pops!!!