Hey there! Sorry to hear you're having a problem with the game. Unfortunately, I'm not from Frictional Games, but I'll assign this thread to one of them and hopefully they'll get back to you.
You may also want to try contacting them directly via their
Contact Page. Perhaps include this thread URL in your post as well.
The only other thing I would recommend other than what you have already done is to reload an earlier save using the Load Game option in the menu, which will reload the level and the scripts, but considering how you're set on a refund, I understand if you choose not to do so.