The biggest thing was the lack of push by our offensive line. Foster just plain outran their D on a couple of plays (and they tackled horribly), but whenever we tried to beat them between the tackles it was a mess. That's a terrible sign for a pro-style team against any FCS team, let alone one of the worst defenses in that division.
We also had a bunch of penalties, didn't rush the passer terribly well, the secondary was mediocre after that first play, the punting was bad (which is an underdiscussed problem), but the biggest red flag was the o-line, for me.
The reason we did so well, other than the huge talent differential of course, was that Lunt was awesome in that game. If he has a clean pocket and his receivers can get separation, he will waltz right through you. Those things are sadly unlikely to be the case going forward.