I had the same bug, but hesitated to reply because I overwrote the "savepoint" by restarting the game with clicking "new game".
Restarting at that "savepoint" shut the engine down, too.


To keep it short: (Sorry, mainly critics for now!)

- the level is too dark, it needs a higher ambient, or more lights. Often it is difficult to see where to go and to see the enemies or scientists.
- my "brother" shot the scientiest - more than one time - when we joined the scientist to ask questions.
- the walk animation of the brother is a bit funny, too short steps!

There are a lot things which are very well made, and a lot that fit together very nicely, but the mentioned issues weakens the impression of the game and the set of tools.