First of all, make sure you don't have any rogue policies enabled. Since you can't configure a mobility group between the WLC and Meraki, this prevents the APs from being detected as a malicious rogue.
Also, pay attention to channels and signal strength to avoid generating interference. This is for the same reason mentioned above (not being able to configure a mobility group between the two).
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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