Any module has a hard resource limit of 16k resources. Any created item, area, placeable, creature, etc. - including hak resources such as CEP - uses 3 resources. What is possibly happening is that you're exceeding the hard resource limit.
This happened with our PW several years ago. We had to trim the excess; useless NPCs, conversations, scripting...we eliminated small areas in favor of large ones. For example, a town might have had 5 buildings that took up 8 interiors, so those 8 interiors (24 resources) would be combined into one area.
We found that even though the module has a hard limit of 16k, that it worked ideally when resources were kept under 15,500.
I don't know the circumstance of your server, but my rebuilding project has been over the course of the past two years to trim all the nonsense generated by 7 or 8 previous builders, going through everything to figure out what is essential and what is not. If you are not using a standard resref naming convention, I suggest you implement one. Backtracking later will be far easier for it.
