<<Spoilers>>
As I complete the last mission, when abbadon's ship explode, my game is freezing, just like the pause was on. I still can move on the battlefield, give orders and use skills, but ships won't move and (i guess) the final cinematic won't launch (I unlocked the steam achivements the first time)
I tried 5 times with different graphic settings, still the same result
This is the first time it's happening in 40 hours in this campaign

Can anyone help me?

Hi, it's a known issue and the devs are working on it. In the mean time there is a workaround if you want to finish the mission you just need to press the "play" button beneath the mini-map to resume the game, this should launch the cinematic and finish your campaign. Hope this helps !