And just to clarify -- I have the output's usage and type set the same as well as the names. There really isn't ANY possible difference I can see in a loaded substance versus the one I save, and yet one works and the other doesn't.
However, I do note I don't seem to be able to EDIT the supplied Substance. I don't know if the file itself is different in some manner or if it's just Read-Only, but while I can see the various outputs and basic information, none of it will load into the window where you could edit it (because, if so, I'd just use it as a basis for a new material and see if THAT would work).