The problem with this statement though is this.
Even though the exe that runs the program cannot use more than 4 gigs of ram (3.75 is what windows shows because of the hal reservations, google it) that is ONLY system memory. The gpu's show as different memory addresses. So dependant upon different setups, the exe being 32 bit is not a problem...
A lot of people say that 32 bit compiled exe's are the problem, but I know for a fact, it has nothing to do with it. What has everything to do with it, is the quality of the coding. And bugs happen, no matter what.