its starting to seem that its just a mix up with game versions and corrupted save files. Main reason i couldnt figure out the solution was that i didnt ever realise that in alpha just loading save file can corrupt the file totally with wrong version.
But, this sitation so far:
I tried to load with given clean save file with regular 4.0 version game: Same problem occurs.
Then i patch game with xp/2000 compatiblity patch and load given savefile which is still in my save folder: Same problem occurs.
But then i delete given savefile, load it again from here to my folder and rename it just to be sure. Load the second time loaded clean save file again: Tadaa, it works

.
Feeling frisky so i decided to test this also with unofficial patch: Tadaa, it works again
So yeh, seems at some point we got all the versions mixed up after all, bit embarressing rly to fall something like that

. My friend is coming over at evening with his laptop so i can make sure that hes using right patches, and hopefully get it all fixed in the end.
And if im correct here and all will start to run smoothly, i have to say sry to you all for wasting your time for something so basic and simple mistake like this, but im still going to thank you guys big time. Without the given savefile i dont think i ever couldnt figure out what was going on

(no matter how insignificant and small error it was X)