[trevius]

Also, a way that I use in some cases that works well for situations like this is to add numbers or pound signs (#) in the name somewhere depending on which version of the NPC it is. Then, you can name the script and include the numbers or pounds and the players will never see them as they won't show up in game.

So, you could name them something like this (I have used this and it does work):
#Bzzazzt
##Bzzazzt
###Bzzazzt

Or something like this (I haven't tried this with numbers, but I think it would work):

Bzzazzt1
Bzzazzt2
Bzzazzt3

Then your scripts will be named after those same names like this:

#Bzzazzt.pl
##Bzzazzt.pl
###Bzzazzt.pl

Or:

Bzzazzt1.pl
Bzzazzt2.pl
Bzzazzt3.pl

If you try the one that uses numbers and it doesn't work, you may be able to get it to work by moving the number in front of the name. Again though, I haven't really tried doing that, but I assume it would work.