Well it's in our old 19.3 game on a dedicated server and it actually took less time to draw it than it would to fire that back up I think. The basic layout is below.
Zombies enter at lower left, climbing as they jump over stuff until they reach the platform where the sledge is. Some of them get to start over at that point!
The ones who get past the sledge start down the corridor where they get 2 acupuncture treatments and 3 haircuts (the floor is half-blocks, and the corridor is 3 blocks high, so blades really are designed to hit Demolisher heads only). If they survive that they turn the corner for more acupuncture. Very few zombies made it past the first set of dart traps after the corner. But we could see (from the firing position, looking down on the ramp) if any were getting close to the iron bars and we'd step over there and mow them down. If it got really hairy, we'd throw the Oh S**t switch and flush the zombies down into a pit to start over (or just bash on stuff down there).
Dart traps (2 high) are red blocks. They are all fronted by arrow slits with iron bars attached to the face. Tripwires are the green 'Y' symbols (some were outside the base on the exterior wall, but base is high up so they're not in any danger). Fenceposts are the blue star symbols. It took a while to sort out the layout and the wiring, but the base was pretty solid. We always had 2 or three support pillars broken out by the end of the night, but besides one time when cop spit took out a poorly-placed switch & relay, we never really were near being overrun. We'd spend horde night concentrating fire on the big guys - Demolishers, cops, wights. The peons would be killed by the darts.