Hi!! First of all, thank you very much for taking the time to write such a detailed response.

I've been experimenting a little bit too and pretty much came to the same conclusion: Carthage reform spam IS the culprit. I tried but wasn't able to replicate your solution though. Maybe I wasn't editing exactly what was needed, but the game would crash and wouldn't even load after that.

So, I got back to script editing and almost came to the conclusion that the script crashed when it tried to build new MICs or maybe place the markers in some trouble cities affected by spam. By some more experimenting with old save games I managed to discover that the crash was also somehow related with the number of buildings in those settlements, so.. I just destroyed some and... reforms kicked in!!! Not the most elegant or tidy solution but saves me like 130+ years of play