Spent also a lot of time today trying to find a good looking crouch/sneaking animation and found something on the Unity Store after a bit. Read a little about animation blending in UE4 as well.
Tomorrow... fully starting the block out and will definitely create more "designer set" pieces as a I go along. I'm also going to isolate unique pieces and try to integrate them into the level (curving stairs at the entry is going to be pretty tough. You can check my map layout in Daily Challenge #2 I believe).