Companions in the OC were unable to multiclass. This is rather restrictive, so many builders turn on unrestricted level-up for their campaigns. However, what if you don't want unrestricted level-up, but you do want certain NPCs to be able to take Prestige Classes? What if you want to allow some multiclass options, but not all? This simple script allows a middle road between a multiclassing free-for-all and the complete lack of it as seen in the OC.
To prevent a character from leveling up in a given class, set a variable named "DisableClass" + name of the class, without spaces (e.g. "DisableClassFighter", "DisableClassDivineChampion") to TRUE on them. If you set the variable "InvertClassRestrictions" to TRUE, only classes WITHOUT the corresponding variable will be disabled (if you only want to allow a couple of classes, for example, it's easier to do this).
Known Issue: If you disable the last class a character took, they can still level-up in it.
This package requires a minor UI modification (to the levelup_class.xml file). Since the new version of this file should go in your Campaign folder anyway, I've left the script loose to be put in with it (you can of course copy it into your module(s)).
10 - A Masterpiece, Genuinely Groundbreaking 9 - Outstanding, a Must Have 8 - Excellent, Recommended to Anyone 7 - Very Good, Deserves a Look 6 - Good, Qualified Recommendation 5 - Fair, Solid yet Unremarkable 4 - Some Merit, Requires Improvements 3 - Poor Execution, Potential Unrealized 2 - Very Little Appeal 1 - Not Recommended to Anyone