Hello,
The Galactic Civilizations III is a great game, keep doing good work 
I've got some issues with GUI, here is my feedback:
1. Diplomacy view, trading:
http://i.imgur.com/iqGZRKe.png
Currently to remove highlighted offer, I've to click on it, select 0 credits, and click offer. Is there any other way? I would like to click less. For example, "right click" will remove offer. Or add "X" button near the offer?
2. Planet view, building improvements:
Double click on item, results in "Rushed" state. Well, I've played the GC3 only for 8 hours, but I've already rushed like 5-7 buildings by accident...
http://i.imgur.com/7odVaKV.png
3. Also, I would like to see credits dialog/window in the planet view. Yes, I know that under the buy button, there will be tooltip with current credits & improvement cost. In my opinion, this tooltip looks like quick workaround to the real solution.
This is all I've got for now, I will add more later.
Thanks
PS. Sorry for imgur links, your forum engine doesn't support inline images well...
PP.