Wow, I played through this yesterday, it's fantastic. This is definitely the most ambitious and aesthetically pleasing campaign on the workshop. I thought your trees looked perfectly fine to me, and the boat was my favorite piece of art, I raved about it to the person I was playing with.
For those that haven't played through this yet I advise you to do so, also there are spoilers below:My favorite puzzle ideas were the flame maze that you have to guide the zombies through and the pathing concept of the mine tracks. The only puzzle we couldn't complete was the many staircases puzzle in the crypts. We went down every staircase on both levels numerous times but never figured out what we were supposed to do and ended up having to restart via save since there is no way out.
Even though it was a beta I found it very polished, however we did find a couple of bugs to report:
In the sewers there a room block off by a fence, you can walk through the top part of the fence at least 1 spot.
In the dank forest there are a couple of places where you can get through all the trees, not sure if this really matters to you since you do have the emergency collosion.
In the area where you have to lure the zombies to the fire you can hit the switch on the right even when the firetraps are deactivated and it will play the 'deactivate' animation.
There were a couple of areas where you couldn't shoot through some doodads such as fences, maybe you wanted it this way but the one I noticed the most was the planks in the abandoned mine.
The music definitely has issues with more than one player, we had town music playing while fighting in some caves and jungle. The spider boss music didn't start playing until after we kill him.
When we got the spider boss down to around 20% he stopped functioning and just stood there while we finished it off.
Great work guys, looking forward the future updates.