There are three files that I've had to run as well as installing a .cab file to get mine working. Check out this thread:
http://forum.ppcgeeks.com/showthread.php?t=25407, post #1. You might also read in OMJ's thread to see what's in his rom re: the gps; since the kitchen now supports Vogue GPS I've not used OMJ's roms the last few weeks. GPS will work on the xv6900; it just took me a little while to get it working. At first mine wasn't even seeing satellites; now locks in seconds.