Pros:

+ A map where you build your way out sounds like fun.
+ The building itself presented a challenge
+ If you know where to go you do get the items you need for a long haul.

Cons:

- There were so many typographical errors in this.
- Most of the real threat came from the tanks.
- Most defensive items were pointless/not well thought out.
- Some constructables were broken or appeared to be.
- Too many items overall.
- Very basic unfinished map; feels raw.
- Needed a lot more work.
- Far from AI friendly.

Conclusion:

Barring a fifty paragraph essay explaining what I think in excess, I'll get to the main points. 1. 4 minutes of holding down the "E" key with your butt sticking out into an unprotected spawning area isn't worth a lackluster secret that can be made in the same amount of time it takes to finish the level quickly. 2. Too many items to be researched, most aren't useful against two tanks and 50+ zombies every 20 seconds. 3. This map needed more time, love, and testing. Simply put, it was a great idea that got about a tenth the time and love it needed. I would like to see more, but only if that extra labor goes into pre-planning, creating, and polishing the experience.