When I start a new game, it will start paused and I cannot unpause it. It can be unpaused if I alt tab, then press the pause button.

 

I think this might be happening if you alt tab while in character creation.

Same here. It's quite annoying.

Alt-Tabbing is both the problem and the solution.  The game un-pauses itself when you return a second time.

Just had this happen. Didn't know that tabbing in-out would fix it. Incredibly frustrating.