> I know that one of the videos comes from a capture card, I mentioned that in the post > with the pics... > > You replied before I fixed one of the links, btw. =P
However it's captured, that part of the game was programmed to have a red background.
The pcb has a defect where it also outputs the background color when it is supposed to be outputting the black level reference value.
Anything (monitor or capture) that looks at that reference value will think that it needs to remove that amount of red from the screen. You can argue that MAME should be able to emulate that, even if it wasn't what capcom intended. But I don't expect you'll get anywhere