In Tip 711 we reported an issue with merging records when the owner of one of the child records had administrative access mode set on their user record. Today the AAM monster struck again.
When configuring the CRM email router, you configure a deployment profile to connect to Dynamics CRM. If you use a user login that has Administrative Access Mode set, the router test will pass, but it will not be able to see or create any records in CRM.
If you have the router set up but emails are not being sent from CRM or incoming emails are not creating cases in CRM, check to verify that the user whose credentials you are using to connect to CRM in the router setup does not have Administrative Access Mode set on the user record.