There are 2 frequent corruptions occurring in Atari DOS file versions of software, Lebeau's "Gauntlet" (here now) is afflicted with both kinds.
Corruption #1 - missing zeros and segment fragmentation, was discussed in comments for the game "Nadral" from Germany. I was an expert programmer and machine code hacker back in the 1980s, and I just whipped up a small segment mapper program in Basic for identifying and repairing (especially so data files can be compared to identify other corruption). Nadral isn't involved, but this Gauntlet is. The unfragmented version was heavily circulated in the past, and the fragmented one here ought to be replaced.
Bad Gauntlet file is 26752 bytes long, the proper version with matching data, is a file 29197 bytes long.
Corruption #2 infecting the 26752 Gaunlet file is the topic of the rest of this comment. There's extraneous bytes at the extreme end of the file, and I'm recalling that Atari DOS tries processing the excess like new segments then usually starts running without noticeable trouble, but often there becomes a single byte of memory corrupted.
An easy giveaway is if the file size is a multiple of 128, such as Gauntlet here = 209 × 128. There's 92 instances at file's end of the byte value $24 or 36 decimal, 92 plus 36 equals 128. This causes the value $24 to be written to memory address $2424 for 18 times in a row, this happens after Gauntlet already began using locale $2424 (decimal 9252) to do who knows what.
This corruption arose back in the day via modem file transfer protocol "XMODEM 128 byte blocks" either a receiver with wrong preference setting, or, transferring from Atari to some other platform maybe PC then transfered back to Atari again. I quickly scanned my file collection looking only at file size multiples of 128, and I found 2 more bad files that came from here at Atarimania.
"Baja Buggies" and "Centipede-5200" are two more titles presently with corruption. These both have $1A repeating at the ends, which occurs a lot, independent of the number of characters needed to form a whole number multiple of 128 in the file size. Same problem, the number $1A gets spat into memory address $1A1A, after each program has loaded.
Someone ought to execute a script which scans all Atarimania for problems. You could test every file size for 128 alignment ignoring everything other than .COM and .XEX so as to not have to "unzip" every archive, just the ones meeting the criteria.
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