The corrupt zombies are due to my really old computer.

This level is much easier with rushing. Hordes and SI spawn behind and are left in the dust. The chainsaw was a lucky find, although it is possible without it. My strat is to corner camp outside the alarm room and melee everything to death with a bat and then go in and shut the alarm off between hordes.

The Jockey was killed by the Hunter?? I have no idea what the hell was going on there. I should have shut the door behind me too.

http://marsh.speedrunwiki.com/Left4Dead_2/deadcenter_3_expert_solo.rar

for HQ MP4 version.