Quite a nice campaign, I like the concept. However this campaign is almost unplayable with the bots as they get stuck in hordes all the time and they ended up dying on every single chapter except chapter 1 (no joke) I was the last one left alive. I decided to just leave them for dead as they'r pretty much useless most of the time anyways. They did enjoy hanging off of the ledges on chapter 3 I think, on the high up platform with the minigun, so I'd recommend extending them a bit more for the bots. Also at the end of chapter 2 for some reason the bots like to teleport under the bridge that leads to the saferoom so a bit of an issue with the navmesh there. I also got a bit of ping lag near the end of chapter 3 and on the finale (mostly due to the number of infected.) But other than that, I quite enjoyed it. You could say that the map design is bland and repetetive, but I guess it's the theme you were going for, so I'll let you away with that. The navmesh was mostly ok, just the issues I mentioned. No glitches/bugs. So overall, a pretty neat campaign, quite challenging and difficult though I must say.