auto-favouriting happens if you listen to a track 5 times. if its your own track it will still happen. its a feature :)
rendering to mp3 for a particular format should come without any post-production. if you just re-render to mp3 without any post then it belongs here. if its an allgear, remix or wildchip format then post doesnt matter.
btw if you want a wav export from mariopants itself for any reason, in mariopants click the save button, then use the drop down menu to choose the filetype .wav instead of .sho. then you can do whatever you like with it from there.