if the engine you're using is limited to one behavior script per object type, you'll need a script and object type for each desired behavior. if you want 100 different npcs, you'll need 100 different scripts and 100 different types.
if the scripting language has the power to query an instance of a type for instance specific data such as an ID #, and can do branching logic on that value, you can use a single branching script for all instances of a type. the script would use the instance ID to figure out which NPC its was controlling. from there, hopefully the scripting langue is powerful enough for you to figure out where that npc is, whats going on, and thus what they should say. this would basically fold your 100 scripts into one big branching monster script, but it would eliminate redundant lines of script code, IE having the same lines of code in 100 scripts. so it would be somewhat easier to maintain.
if you can't do a branching script, there's still the possibility of making a script generator. you would give it a list of high level behaviors, and it would generate the script code for them. a slightly faster way to generate and maintain 100 scripts.
a variation on that would be to have script code snippets for each behavior, and use batch files with the the copy+ command to concatenate them into whatever kinds of scripts you need.
obviously, any script will somehow need to know which NPC its controlling, via some ID info its passed or looks up, or by the object type (for one type = one script).
This reply was very constructive. This scripting language is more than powerful enough to test for an ID (or any variable) of a an NPC and can have virtually limitless scripts to reference from, or call functions from. Are you saying that I should create a separate script (such as a singleton) that will always be running, or listening, and for the NPC script to pass its parameters to a function on the external script signaling it the details it needs to make things happen?
I guess my question is, how could I use that external script to manage 100 different behaviours for 100 different NPC's when they all have very different conditions? Or am I missing the point?