Pros:

+Unique attempt at a Hunter skin. 
+Nice to see someone using white instead of the waves of black or purple. 
+ Decent first attempt. 

Cons:

- Very poorly done. I get that it is your first mod, so this is just a minor point. 
- Doesn't change much. Just a hunter in a white jacket with the Deadmau5 head on the back. 
- Copyright. They've been cracking down on copyright lately, and this could cause some trouble. 

Conclusion:

Honestly, this could be worse. An alright first attempt, but this should be used as an example for later mods to up the quality. 

Pros:

+ Good voice acting.
+ Nice use of the train at the finale. 
+ Good atmosphere. Made me feel like I was in a zombie apocalypse, which is more than I can say for most mods. 
+ Unique use of the tank on the false safe house was nice.
+ Pain Train and Homewrecker are great melee weapons that fit well with the L4D atmosphere. 
+ Good use of music added to the feel. 
+ Survivor chatter. Most mods usually don't add any thing beyond the usual, so I appreciate this.

Cons:

- Finale felt close-quarters. Not a real con, just personal preference. 

Conclusion:

This is, by far, one of the best campaigns I've ever played. The gameplay was smooth, the atmosphere was intense and realistic, and the custom modifications added in to this were excellent.  I look forward to further installments from this use.