Race Specific improvements

Playing as the Altarians, building the Doomsday generator.

 I got invaded on said planet. Obviously this improvement was demolised for the invading race (the all conquering humans).

The very next turn I took back my PQ26 planet (the very nerve) 

But I couldn`t rebuild my Doomsday generator.

Now I am slightly miffed. I have put up with your politeness for too long ,

 prepare too feel my wrath from the wraith MK II.

I don`t know if this is a bug for all race specific buildings that have been demolished during invasion.