You can verify the problem when using the Disk Manager cartridge and do a disk check. It will fail after half of the tracks.

SVN r5817
ti99_4ae driver
Pitfall (Floppy Disk)
Disk Manager 3 (Cartridge)

I can boot the disk and play the game

if I check the tracks with the Disk Manager, I get errors.

1st Screenshot: SVN r5817, 2nd Screenshot: official MESS 0.134

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