Cool idea but I too ran way too soon out of batteries. I also got stuck when trying to leave the basement again.
You definitely got the horror atmosphere down though! I really enjoyed the setting. But there was something weird (not sure if intended) going on with the UI/"E"Buttons. They were kinda jumping around like crazy when moving the mouse.
Performance was pretty good too. Did you work with level streaming?
I really suggest adding more batteries and allowing the camera to run longer with one battery. Then this could be a real fire game! Well done!