What game version?

I've tried all these versions:

Win 32, v 0.11.22
Win 32, v 0.12.8
x64, v 0.11.22
x64, v 0.12.8

Can you upload the save file (if you have one) or the scenario you're using?

See the attached file: Gordon.zip

Can you tell me the steps you do to make it happen?

1) Start ...

Playing a custom map/scenario , the game hangs or freezes when trying to save, i.e. I click the SAVE button and it darkens and nothing else happens, the game becomes non-responsive.
However, the Auto-save feature works fine.

When playing the pre-made scenarios , SAVE works fine 100%, the problem ...

When I try to SAVE the game it causes the game to hang/lock-up.
In other words, the "Save" button goes dark and nothing else happens and the game stops responding (resulting in me having to kill it in task manager).
I just upgraded from Windows 7 (x64) to Windows 10 (x64) and I've tried:

Setup ...