Mark's Bigdisk images should Just Work.

If they don't, then there is a problem with the serial cable, the serial port, the serial port settings in the BIOS or in the device manager, or there is a problem with the software you're using to upload the builder to the player.

There's also a chance it's hardware trouble on the player itself.

There's a remote chance that the builder file itself got corrupted on download. But we haven't seen that happen in along time. u