Maybe I’ve missed it, but is it possible to configure the destination of an aux channel on a macro page? It seems that there is no assignable parameter.
You’re right there’s no assignable parameter for this but you can use the Mixer Channel template. If you’re only interested in the output selection you can edit the template and delete things you don’t want/need.
It also depends on which aux channels you want to control. If you mean the 4 global aux fx channels that are common for the whole Halion instance, I don’t think you can do that from a macro page. But if the channels are part of your program then the Mixer Channel template should work fine.