Have the same issue ...but my corruption occurs after I hit end turn button and for some reason the game get stuck at Ikko Ikki banner and the game just block ..so in order to continue I have to press ALT TAB buttons combination and to close the game manually ..I get back in I hit the end turn again and the game works just fine except that from that moment on all my saves games are corrupted
..this occured in my DartMod turn 75 ..so I dropped dead my campaign as Shimazu and started a new one as Hattori ..hopefully I won't have the same issue