if anyone here understands libusb programming and wants to help me solve the issue of my treo 90 not playing ball with pilot-link, please check this github issue where i've provided more info and contact me for a full hotsync transaction usb capture https://github.com/desrod/pilot-link/issues/13
i managed to make a little bit more progress, now it seems like the treo's response matches that expected from a regular palm device, but still doesn't hotsync: https://github.com/desrod/pilot-link/issues/13#issuecomment-1299023698