Did that last night, only change I've made was to increase the money I have by 1. That's all.
Using latest Checkpoint & Edizon on SX OS 2.2.1 - both programs produce same error in-game.
Tried to eliminate all I could think of before posting here, which is mostly starting fresh each test, and trying with only one, minor change.
By the way, I'm able to restore a working save each time - which I believe that eliminates the possibility of me doing the backup&restoration process wrong (meaning, I'm able to load my backed-up save and continue playing unmodified, save again, test again).