Ah I see. I have not learned any codes within MC. My case has an iMon IR receiver and key mapping software, so my harmony sends a MCE button press to the IR receiver and then iMon converts it to the the keyboard shortcut for the focused application, so I'm not actually using the MC IR remote function at all.
I'm looking at trying to write an AutoHotkey script such that when I press the "E" on the harmony, harmony sends a MCE "red key" button press to iMon and iMon converts this to a hotkey, say control alt F, which if a MC window exists, forces that window to the front. But I've not managed to get it to work yet.