First, thanks for the responses.

I did try the 'Return to Factory Settings' suggestion, but the MIDI Styles I had been trying to load the demo songs for, still registered 'Not Found'.

Out of frustration, I filtered the StylePicker to include just the MIDI Styles and started to attempt to load the song demo's one at a time. The first 4 styles failed, but the 5 style loaded as expected. The weird part is they were all from the same style set. Continuing down the list, it seems totally random on which will load the demo songs and which won't.

I do appreciate the help, but at this point I'm going to give it a rest. I get the feeling that something this random is going to be impossible to track down.