Ruler Designer Doesn't Work with Charlemagne

[f1nalstand17]

I recently purchased Charlemagne, and it seems that the ruler designer doesn't work for me anymore (it did before I had Charlemagne). Is there a work around? Is this a known bug? I also selected the earliest start date (which came with Charlemagne).

 

[PeterSkager]

Did you use someone specific as the base of the ruler design? It should be completely compatible and I've seen no problems with it previously