Multicast Group setup with McGroupSetupReq

Hi, is there any progress for the stand-alone remote multicast group implementation? I checked the code and found the remote multicast group setup is already there which also seems convenient enough to replace the current multicast group.

My project needs it now and if there is no recent plan of this feature, I may implement it on my own. If so I’d like to know is there any concerns or difficulties I fail to see here? It would be very helpful to me.