I think the recording should start and stop when you would like because whenever I join a game it immediately starts recording and when I press ctrl+f4 it says, "bookmark start," then I try pressing it again and it says, "bookmark stop," even then it still records. Please let me know if I am doing something wrong at lomecheesefoam@gmail.com.
I really think this should be an option. Because it takes processing power to record games, it does sometimes make my frame rate stutter at times and it can be awfully distracting.