RPL Connections - Automatic Updation

I am trying to use the update connections functionality to connect two RPLs. This does not work for me.
In the update connection dialog I see the attached dialog box.
In the help page I read that a prerequisite is that all involved ports in the REC elements have corresponding ports in the RPL elements. Does this mean that there should only be port connections between the two RPLs for this to work? My RPLs have multiple ports out of which only a few are connected between them. The remaining connect to other elements of the diagram.
Thanks!

Update Connection.png
Update Connection.png