The day after |
So I've destroyed last enemy ship and occupied his last colony. I've lost the contact with him, but strangely he isn't out of the game?
I've noticed that the population on the planet I landed on, although loyal (pacified by my ground troops garrisons) are still marked by his banner. Even more, I'm getting his race bonuses there. Is this normal?
On the other hand his race immigrants on my new colonies (founded by me) are marked by my flag and don't get any of his race bonuses.

I had something happen like
I had something happen like this, in my game I took over with troop the last colony and then later on (several turns later) i noticed that there was now two types of inhabitants. I can't remember the specifics of what told me there were two different types of inhabitants, it was something like: his race but my banner with his race and his banner (but there wasn't any fighting on the planet). Like I said this was a long time ago and can't remeber the specifics.
SEV, more than a feeling.




Their society originally has nice 15% research bonus, which still applies to every conquered alien colony although this time as a 
Very Strange
That is odd behaviour. If you're in control of his colony, it should act like any other colony of yours where his race is located. I've never heard of this bug before, you should send the save file to along with a description of what's going on.
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Watch for my mod - codename: Dimensions - coming by Summer, 2007!