That one was super easy, upon boot game indicated 2 bad RAMs @ C11 & I5: I replaced them but the game hanged up. RAM @ C14 was faulty too (although indicated as OK).


Then sound was glitchy: bad RAM @ F5 (not tested on startup, can't be tested in test mode). Sound was still glitchy: bad ROM (27C256) @ F7 (can't be tested in test mode either).
Game repaired.