After killing myself on level 119 (solo game), I began to wonder about alternate routes.

You can actually do the run in a circle at the Fishing Hut and at the Storage Hut.

The fishing hut is almost as easy as the Comm Room, the Storage area is harder.

FH; Run down the middle of the swamp to the stairs of the hut, wait until the zombies come close and run down the wooden walkway to the area near the Flogger and then repeat. There is plenty of room there to get around any zombies and repeat the circle.

SH; Run down the right side, when you get out of the hut, stay left along the wall or the swamp will slow you down. When you get to the stairs, wait for the zombies as long as you can and then run down the middle channel to the main building, repeat.

I have successfully used this running around with 2 people. Have one run the Comm Room Circuit and one run the Fishing Hut circuit.