At the end you have to defeat the Ferengi Captain and beam him up.
After defeating him, i cannot beam him up, no symbol to do this, nothing.
I tried the whole mission 3 times and every single time i got the same problem.

This is because you "killed" the Ferengi and dropped his hp to 0. When he reaches about 50% and offers to surrender a white "beam out" option will appear on the right side of your screen, you have to hit that and accept it before your away team kills the guy.

the thing is, you can't kill him if he's at 0hp he did not go down - he just stands ****ing in the room and you get the info to tag him and beem out.