From my limited experience, all I did to get the VirtualMIDIsynth to work was to simply install it. It then showed up in the BIAB MIDI output driver dialog box and can be chosen while unchecking Use VSTi. Then if you go to your start menu and launch VirtualMIDIsynth, it gives you a very simple dialog to add any soundfont files you have.

Geeze is it possible I have helped someone?!?!!?