Sorry to hear that. As far as I know, Renpy 7.5 is still compatible with Windows 8 and x32 bit systems, but may not be able to handle low amounts of RAM - I think it requires 500mb or so? That said, I'm not super knowledgeable about that stuff, Renpy handles most of it for me. Are you able to play other recent Renpy games?
Yeah, none of these issues happen normally, in web or downloadable. I hate to say it, but it sounds like renpy might not be quite as compatible with older/weaker systems as they advertise.
What kinds of crashes are you getting anyways? Like are these actual error messages, or the game shuts down, or what?