Hi,
I struggled with my sandbox environment, how to "turn off" Management Reporter connection. My sandbox was a copy from production environment, and for testing basic AX usage (no Management Reporter needed).
When I started MR from GL, for example, it ran the production instance. Thus (as we have same users in Sandbox) there lies quite a risk for confusion.
Finally I checked from code what action was started here, and noticed that the code reads the Legderparameters table - and yes, one can find a reference to the MR Service in column MANGEMENTREPORTERURL of LEDGERPARAMS of each legal entity (mrd://?ServerConnection=http://servername:4712/&Company=XXX). Deleting the reference seems to reset the MR setup :)
Have you found this parameter somewhere in AX client? I tried to look after it, but wasn't able to find it.