I don't know what else to do other than keep telling you that the game runs completely fine without the CK2plus mod. Simple comparison with only one variable being changed, this having the effect of creating instability. Logic dictates, that this variable is the one causing the issue. And I have stated this in my very first post -.-
I have recently upgraded my PC by switching out CPU, mainboard and RAM to newer models, I previously used a core 2 duo, now I'm using a core i7 and RAM at 8GB instead of 4. This involved a new windows installation as well, so the system I have now is very different from what I had a few months ago. And guess what - back then, the situation was the same, CK2 ran fine without CK2plus besides it slowing down after a while due to the dated CPU, but was unstable with the mod. Stability may now be better than it was before (I can confirm that actually, and thanks for that btw) but that doesn't mean it's completely fine now.
One crash every couple of hours still puts a dent in the experience when you are used to not having to save very often, and having to reload to a 5 year old autosave in the worst case scenario can (and in most cases will) lead to vastly different timeline than the one you have lost. Then there's the case of a save game being corrupted, granted this might have been a very rare freak accident but evidently it does happen. The problem being waved away by the first one who doesn't happen to share it does not exactly make this feel less frustrating either. The only reason why I still even try to put up with this is that I think the mod is just awesome other than the obvious issues.
As for any other mods I am using: besides all the official DLCs (yes I'm a sucker for those) there are two more things I always slap on top of the game, those are the new borders, rivers & textures mod (NBRT) and the keyboard shortcuts and interface adjust mod. Neither of which change the checksum and both of which are active when I do not use CK2plus - which is when, as I have said multiple times, the game runs without issue.
I have uploaded a zip with two of save games into my dropbox:
https://www.dropbox.com/s/fvsoelal345x7dt/ck2plus_saves.zip?dl=0
the latest one is the one that has been corrupte, i.e. won't load any more. I have attached the second most recent save too. I hope this helps you somewhat, and I do hope you now have enough information about my case.
@LordPeter: I have chosen the name just because it sounds grumpy, I only later realized that there's a famous German youtuber with that name. So yeah I stole his identity, maybe subconsciously from having heard the name before but not having paid attention to it.