Doc about VMS support for GS/XG modes?

Hi,

In the VMS options there is a GS/XG panel with "override received MIDI SYSEX messages", what does this option do exactly ?

Also I read in another thread that VMS/BASSMIDI can recognize GM2 or GS System ON  sysex messages. Does it recognize Set XG mode ON as well ?

If I switch VMS/BASSMIDI in GM2 (or XG) mode, how are the bank select messages translated ?  (GM2 bank select method=MSB+LSB, but SF2 bank select method=MSB only...).

I'm asking these questions because I'm writing an .ins file for a custom .SF2 for my app., and I need to be able to select drums/perc. instruments on more than 1 channel (e.g. channel 10 AND 11).

Thanks in advance for your help!