He can appear at the start of the Infin-ID layer so don't waste time going through checkpoints. If he doesn't show up in the first 2-3 minutes just die and start again.
I contacted press play about the issue. They are going to be releasing an update soon that will fix the mouse problem. Happens to some people and not others.
Two of the achievements for second assault dlc don't unlock on the Xbox One. The achievements are Risky Business-Kill an enemy flag holder while carrying your team's flag in CTF and Blind Bomber-In a round get 5 kills with air vehicles in Gulf of Oman. My friends and I have done the requirements several times with no luck.
Not sure about other people, but I ended up having a problem with having it register for both consoles. I contacted Xbox support and they did something that made it register for both.
I'm not 100% sure but I spoke to EA customer support about this and I was told that premium purchases are linked to origin accounts so if you are premium on 360 it counts for Xbox one as well. He didn't tell me there was a cut off date. When I check my BF4 profile on battlelog it says I'm premium for 360 and one.