Hi @Chris.Pierce ,
you copied the dll on the SCSM Management servers in the folder C:\Program Files\Microsoft System Center\Service Manager
?
Best is to copy the file before importing the MP but at the end it doesn't really matter.
Did you restart the SCSM services? if not please give it a try.
Also clearing the SCSM server cache might be an option.
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Regards
Andreas Baumgarten