Hello and I am sorry if I'm posting where I shouldn't, but I just wanted to let you guys know, maybe it happened to you too.
I just received multiple crashes this evening, after a minor update(dunno what the update was about, it automatically installed after i clicked) I entered the game as always, loaded my game against AI, and the game first crashed when I was in the middle of the battle against an AI hero, then I loaded the game again and crashed when I cast Town Portal, so it appears to be random.

I'm attaching the ss of the beginning of the crash log if it helps.

Have a good one, and thank you !

If you're getting automatic updates, you must be using the galaxy client.

Try using the normal offline installers that don't need a client to work.
Download it from your account here.
https://www.gog.com/account

Ignore the blue 'Install For Galaxy' banner, and download the normal installers underneath.

Hope this helps. ( :

Apparently is related with the HD Mod, have you tried to update the mod? Like download and re I install the mod, that could solve your problem.

Or, according to OP's log, it could also be Horns of the Abbys that's at fault. Downloading HoMM3 HD 5.2 RC28 and performing a clean install might solve the problem. Complete -> HotA -> HD-Mod, in that order.

I received a minor update just now, so far so good, if it will continue crashing, I will follow each of your instructions, thank you very much !! ^^

Good to hear is solved!!!