When using Cakewalk and any Roland expansion boards (SR-JV,SRX) you have to first get the INS file for that card and then manually edit the INS file for the XV and add the contents of the expansion board's INS so it will show up correctly. There is no other way around this because of the fact that each expansion slot has its own bank number and 2 people could have the same cards, but they could be in different slots.
Kind of a pain in the butt...
I had to do it with my XP-30 and the Vintage Synth board.
Let me know if you need more specific instructions.