Overlord question

[Pulaski]

Finally finished my first Overlord game. I have to say I find the inter-city battles to be just plain annoying.
My question is does the depreciation of buildings have any effect on their abilities/bonuses? Or do they just disappear when they get to 0/100?

Also I had a weird thing going on where I ALWAYS had two battles in the same turn, consistently.

This coupled with my previously mentioned problem with IT 1 makes me wonder if my PC or install has something wacky going on.

[capnq]

Also I had a weird thing going on where I ALWAYS had two battles in the same turn, consistently.

I had that, too. It only seemed to happen after I'd built the watchtower.