I don't know if i understand you correctly, but msg plus! already lets you have 5 panels and you can put the smileys on any panel you like (plus > preferences> message helpers > quick icons (tab) check "enable quick icons panel" and "display the panel....",under Panels configuration click the configuration button to sort them as you like.
edit: after you enabled em, you can do as raceprouk said (typing: ( will make the panels show, the numbers on the bottom of the panel can be clicked to switch panel)
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