I think the .gvm/gvm.store file is pretty much in a closed format. If you hexdump it you can see prc and pdb data in there, but the content's been reorganized a bit. It could be that the file (except for, I guess, a header, and maybe a "ROM" part) is laid out a bit like a physical Palm PDA memory image. But I don't know if that's documented by anyone. FileZ seems to be able to interact with it through API calls. But, as FileZ can't actually send anything through BT or otherwise (unlike on a physical Palm PDA) there doesn't currently seem to be a way to get e.g. .pdb files out of there.. which is a pity. I can easily transfer .pdb files from my T3 applications to the N800/GVM, but I can't transfer them back.