Here are some bugs I have found in the V3 beta.
Paxton's Emporium
Paxton's Emporium has this in its xml description:
<IsGalacticWonder>true</IsGalacticWonder>
<IsColonyUnique>true</IsColonyUnique>
This description indicates this is “The one-of-a-kind intergalactic trade show ….”, so why is it also one per colony.
Also, in one game I had a chance to build it, but someone beat me to it, and it was deleted from my build queue. After a number of turns (don't know how many) of it not being in the list of things I could build, I found it listed again as something I could build. I started building it again, someone beat me to it again, and it was deleted from my build queue again. Why was it available to build the second time? I have a save that shows it being built the second time. I have looked through all the other planets for the first one that was built, but I was never able to find it. I don't know if that means I missed it or if something happened to it. If something happened to it, I have no idea what it could have been.
Build More Than One of One-Per-Race Planetary Improvements
In my post about Crusade Bugs – Part 2, I reported about this. The Import Export Center can be added to the list.
Universal Translator
Early in a game I can't understand anybody because I don't have Universal Translator. Later I can understand them, but I still don't have Universal Translator. I know this is for the conversation windows that pop up over the galaxy. I'm not sure if it allows me to make trades in the trade window. I get the impression that if the alien race has Universal Translator, the game treats it like I also have it. This does not happen in Crusade.
AI Starbases Mining Bazaar
I first noticed this in Crusade. I don't know if it started then or existed in Mercenaries. The AI love to build starbases to mine/research Bazaars. If there are resources nearby, the AI will build to get as many resources as possible as long as it can get the Bazaar also. If it can get more resources by leaving out the Bazaar, it will choose the Bazaar instead of the extra resources. If there aren't any resources near the Bazaar, the AI will still build a starbase to mine/research it.
This seems to be much worse in V3 beta. I have some saves that show the existence of this, but not why the AI did it.