Pros:

too many tanks ,witchs
very good map ,campaign 
bot will take medkit for themselves at the start of the campaign.
Finale like no mercy but whole layout is good 
finale tanks will might glitch and might struck 

Cons:

no much more problem at the campaign ,good to play ,there is no need to update for it , keep it up for the nxt time , i hope you might create one more like this campaign in l4d1 

Conclusion:

Nothing to say about  this campaign ,i give it 90 out of 100