I am not sure if the building errors have been completely fixed. I have a game going with the 2.51 version without the extra civs. I was happily building harbors when I got an event that asks me to build 9 ports. Each time I built a port, the harbor came back as an available building. Furthermore, before building all 9 ports, I built a few commercial ports. Unfortunately, this wiped out the ports so I have to go back and build a harbor and a port again.
First of all, once I build the port, the harbor should be upgraded and still present so I do not have the option to build it again. Secondly, if asked to build 9 ports, the commercial port should not "destroy" the port so that the game thinks I haven't built it.
First of all, once I build the port, the harbor should be upgraded and still present so I do not have the option to build it again. Secondly, if asked to build 9 ports, the commercial port should not "destroy" the port so that the game thinks I haven't built it.