I can't answer your questions. I haven't seen this bug firsthand, so I rely completely on feedback. However, it appears that once the BIOS has copied itself to the drive, this copy remains in place. Therefore, if the drive is ever re-examined by the BIOS, the existence of the copy should prevent the problem from recurring. This means that the copy must be outside the user partitions, beyond the last logical cylinder. This in turn suggests that BIOS must be file-system-aware. If I'm correct, then this would beg the question, if the BIOS can correctly copy itself to the uppermost LBAs, then why does it incorrectly truncate the drive?
If you would be prepared to examine your disc with a hex editor, you can search for text strings that appear in your BIOS image. This will tell you where the BIOS copy was written.
You can use HxD.
HxD - Freeware Hex Editor and Disk Editor:
http://mh-nexus.de/en/hxd/Launch HxD. Go to Extras -> Open disk, tick the Open as Readonly box, select your Physical disk, and click OK.
Type Ctrl-End. You will now be at the end of the physical drive.
Select Search -> Find, choose the Backward radio button, Datatype = Text-string, and enter the search text in the "Search for" box.
You could search for the following strings, or parts thereof.
"Award BootBlock BIOS v1.0"
"Can not Find BIOS Image in Hard Drive or Diskette"
