I've created an 8 track looper: for every track there is an aux channel with a "Looper" plugin. Then, in the actual patch, there is one audio channel for each aux channel.
I've also created some buttons to fire Looper functionalities. For seven of those tracks, the mapping works nicely. For one of them (the number 7) whenever I try to map a button to a Looper function, I get the "PDF Page". Moreover, whenever I change something in this track (number 7), MainStage fails to save the project, and I have to manually close it.
I've also tried to delete all the buttons/controls and the channels for that track, recreating them again manually, but always with the same result. Is there any way to "manually" edit the concert and/or to see what is hidden that may lead to such issue ?