I know from trying to share information from cubecart with coppermine picture sharing site that sharing the database requires a "bridge" which is done by php. My guess is that you'd need someone (a programmer in php) to accomplish this with a forums and vshare. It's possible with phpbb and coppermine (it comes with coppermine installation to bridge with phpbb), I have no clue how it's done between any forums and vshare.