[simoncion]

I was really hoping to hear from the OP, but I'll address this tangent.

These installers would be an issue whether or not one was running Steam. If you were installing from a disc (heh) rather than using Steam, all that installation stuff would have happened while you were running the installer on the disc (with Admin privs).

So yes, installers that potentially install stuff under %PROGRAMFILES% and %SYSTEMROOT% will require admin privs. Unless you change permissions on the associated directories and registry trees, there's no way around that.

AFAICT, Steam itself (and, indeed, many games sold through Steam) does not require admin privs. Maybe I'm wrong about this. That's why I asked the OP for clarification.