I can't go out of the nest


I'm assuming your talking about Empires of the Undergrowth? If you are, then this is in the wrong category.

If this is a post about EotU, then if after the game crashes, a window saying "An Unreal process has crashed: UE4-EotU" pops up, you should read this post: https://forum.slugdisco.com/index.php?threads/important-how-to-get-crash-reports-to-us.5231/
If not, then you might want to give some more details, like if it was the story or freeplay, what you were doing at the time, etc.