I installed the WMIPerf_MSSQL Zenpack (seemingly) with out issues.  However, the zenpack is supposed to install a zProperty called zSQLInstance and this didn't get installed.  I tried to un-install the zenpack and re-install it but it zenpack --remove fails saying:

ERROR: zenpack command failed. Reason: ValueError: The property zSQLInstance does not exist

I've tried numerous times to add the zProperty following this how-to but it just won't add: docs/DOC-2347.

What's interesting is when I run zenmigrate --list I actually see it calling my migration script to add the zProperty...but I never see it in the UI.  Any suggestions to get this zenpack working (or just removed)?  Has anyone else seen this issue?