Yup, there was a bug in the Garrison node of the BH tree that caused serious problems in City Defense operation. Omg, this is so good. Naval Superiority was hardcoded at value 100, which was too low to produce naval units effectively and start this operation. Finally naval battles have a chance to actually happen. I am curious how they did it. I mean, in the engine or somehow customizable. But this will make wars much better executed if done properly.