This sounds like they updated their scripts by overwriting the old script, yet kept the same exact NKR. So any old projects would link to the newest script, but if there were structural changes in the instruments themselves (i.e. groups, effects, modulators added or removed), this will break horribly.
There are two proper ways of dealing with this situation:
1. Make your update a completely new NKR and make only the updated NKIs point to it. Old NKIs (from old DAW projects etc) still point to the old NKR. This is what NI does when they update their libraries
2. Make your scripts and assets with different filenames per product update, keeping the singular NKR in your library. This way old NKIs (from old DAW projects etc) still point to the old scripts and assets, and freshly loaded updated NKIs also get what they need. This is what I do for the most part.