Well yes, there seems to be no good alternative to a full grown versioning-system and even with that, we would have to deal with binary's, if I'm not mistaken.
I was referring to the source-files we are developing, using the rpg-maker. It would be nice if there were some tools to patch these files in case an other developer changed them, like you would do in "normal" programming-teams ;) ('patch' and 'diff' are some fundamental unix-utils to do so, jfyi)