Thanks Mateos, glad you liked it.
The problems you encountered are an issue on your PC. In total, One 4 Nine has now been downloaded around 250,000 times, and I've not previously heard of zombies stopping when bile is thrown, so the problems must be on your setup not related to my campaign.
Unfortunately Valve's vpk filesystem is creating lots of conflicts with custom mods and older campaigns (read my response to StoneCrowUK for the full explanation).
I remember one guy had an issue with no zombies at all moving in any level, and it turned out to be due to a completely different mod he had installed (a custom Zoey with red hair). He disabled his custom Zoey model and then my campaign worked no problems.
I suggest you follow the steps I provided to StoneCrowUK, particularly go to Extras->Addons in the L4D2 menu system and uncheck all other mods you have installed, then try again. I'm pretty sure it will then work for you without any AI or sound problems.
As for the zombies only being able to attack from one direction during the finale, it was intentionally designed like that. It would have been too much for some players to have their vision obscured by the graphical effects while being attacked from all directions. You may well have found it too easy only being attacked from one direction, but other players actually told me it's too difficult. :) I think the current setup is a happy medium.
Hope that helps. Cheers.
keved
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