I'm doing it exactly as Kees describes, except I have two RPC-1 cards so 2 RBUS in/outs from my VS-2480 to my computer. I run it into REAPER. I only just started doing this, as it took a bit of fruitful hunting around the Planet members to get a 64bit driver for the M Audio (thanks again BmC).
SO on the OUTPUT ASSIGN (upper right) part of EZ ROUTING, I have RBUS 1 outs 1-8 connected to 1/2, 3/4,,,to 7/8...then RBUS 2 outs 1-8 connected to DIR 1/2....to 7/8.
I've also connected the RBUS 1+2 in the PATCH BAY (upper left). ,,,using tracks 9-24 connected 1-8 on each RBUS. Make sure you click the SELECT coloured buttons to correspond with the RBUS input tracks. I leave the COAX and OPT IN unconnected.