USB booting :: usb install problem

i'm trying to install dsl to my tevion 512mb mp3 player (I can't find my usb pen). when i select to install as usb-hdd, it installs fine, but my computer won't boot it (says that it is not a valid boot floppy or something like that), but when i try to install as usb-zip, it fails when it tries to partition the disk.

why can't you find your usb pen?

original here.