The Harmony client is a Beta level. I will setup my RemoteLinc and see if an Action using the RemoteLinc button can be created under the Harmony client. It probably can be done under Harmony as that client is pretty far along but if not available under the Harmony client you can define the Action using the HTML interface. I will post back the results of the Harmony test.
Can you detail what the problem was attempting to do this with Harmony.