Bill ... I tried it ... it recognized the Main Songbook, but did not recognize any of My Custom Songbooks ...
Here is the response I got from KORG:

"My sincere apologies for the delay in getting back to you. Which SongBook Editor did you download? Did you use the one for our older products? At present there is not a Pa900 compatible version of the SongBook Editor. If you were using the download for the Pa800, that would explain the incompatibility issues that you ran into."


I wrote back saying that I used the Pa3x version, and asked if they were working on one for the Pa900 ... I'm waiting for a response ...