Each new instance of RMX has the standard mixer controls enabled for host automation.
If I load a midi learn template it just adds the template assignments to the already present mixer assignments. If (like me) your template uses different host automation id assignments for mixer controls they appear twice in the show all.
Of course all this can be solved by using the Clear All command first, but it seems to me that loading a new midi template should wipe any existing assignments first and then load the template fresh. Is there a good reason RMX operates in this way?
In any case, TIP: Use CLEAR ALL before loading a midi learn template.