I'm playing the alpha for 6+ hours now and and I encounter a few problems that were already reported by other people in the forum... But I think I just found a new one... I can reproduce the problem consistently in this particular match (save game at: https://dl.dropboxusercontent.com/u/31557345/Auto%20Save.GC3Sav).  

I was fighting several staked ships in the same hex in the same turn, and after destroying 26 stacked ships (red circle in the image), I got my other fleet and attacked the another set of stacked ships (blue circle) in the same turn. After destroying 5 ships/fleets without problems, the 6 one always freezes the game in the 'Confirm battle screen' (second picture). Then I have to kill the game...

If someone download the save and can reproduce (or not) the problem, I think would be useful