Hey, Experiment and I have figured out the checksum that MW3 uses for their campaign saves, and we decided to make a tool. You can edit the DVAR's in the file by HEX editing it, because we still have not mapped out the save enough to list/edit/insert DVAR's. Hopefully we will have that tomorrow or so. Special thanks to austin12456, for telling us it was Adler before we tried reversing it 0_o.
Enjoy the UI. ;)
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