I imagine it will work... However, not sure of how useful it will be since it won't recognize any music on your SD card. You'll only be able to play songs on your GVM partition.
I was unable to get it to work and even if I got it to work, the lack of access to the SD card renders it pretty useless. It now says on their web page that Pocket Tunes is useable for Internet radio only.
Yeah, there are some significant differences between Palm's version of the OS and ACCESS's. In particular, both VFS (removable file systems) and the media subsystem are different enough to cause problems. I'm a little surprised that PocketTunes works at all, really.