CabooseFTW

Im sure this has already been talked about but after getting bored searching the internet for a while, ive turned up nothing, so here it goes: I recently got an electronic version of Halo MCC and since my internet is crap it took a long time to install. But now that it has, I go to play one of the campaigns, and if i do custom start the timer ticks down to 0 and then I just sit there. If I do quickstart, I select difficulty and it locks up the game and i cant do anything with it. Little advice or help would be appreciated, thanks.