Thanks and indeed! Worth saying that my real hardware right now is my CD32 (since my main A1200 needs recap and I'm afraid to switch it on lol).
About Vampire Killer, it has the keys to open doors and allows backtracking/free roaming, which is a thing I'd probably add here (specially on ladders, as jumping from one in a 'bottomless level' results in losing a life and that's not intuitive despite being what happens in the NES original - difference there is that you can't jump from a ladder but you still manage to fall from them sometimes :) as shown in the linked video below)