Thanks very much for your feedback.
Apologies about the Zulu vanishing in chapter 2. He either ran through the building and was hiding around the sandbags somewhere or exited the map entirely due to a buggy tile collider, both of which have been fixed.
The holes in the wall are a bit tricky to make use of, but if you can kite the enemy to follow you, you can run into the building and shoot him as he goes past. If we had more time we would have created more situations in which you could effectively use them.
I hope you will be able to play again and make it past chapter 2.
Cheers