Cities I conquer start with zero health: intentional or bug?

[vampireboot]

I started trying this mod today, and I've generally liked the changes, except for one very frustrating issue that may or may not be a bug. Whenever I conquer an opponent's city, the city ends up with basically no health and restores only over a long period of time, meaning that the opponent can take it back immediately with any loose unit around, causing me to lose my unit as well as some more population/buildings in that city.

I've tried to keep it from happening after learning about this tendency, but it can be very impractical to stop at times, such as with fast mounted units, or, in one especially annoying case, with a random embarked unit hiding outside my line of sight. Now, as if that weren't bad enough, my opponents don't seem to be playing by the same rules. Whenever they take a city back from me, the city immediately heals back up to around the 75% mark, much like in vanilla. I've had to take the same two cities three times each so far, at basically full strength each time, and it's testing my patience.

Is this a bug? Or is it an intentional feature? If it's intentional, how do I get the city health back up immediately like my opponents are doing?

(I've also had the no barbarians bug, but it looks like that'll be fixed in the next version.)