Funny, I am sure I answered this
1) Ketron have never been big on this but have always provided the ability to back up to disk or to a PC. Same currently goes for SD7
2) Ketron themselves. However there are third party style sellers around but I cannot comment on the quality.
3) As of this moment it os only possible to link a PDF music file to registration, however Ketron kindly agreed to add the ability to link JPG/BMP to registration with the next OS update. To do that you simply bring up the music on your display, make your registration and save it. next time you call up the registration the music will automatically be displayed on the screen.
If you want to use two pages as we have done, easiest way is to set your camera resolution to a lower setting (or document setting) photograph the two pages next to each other and copy it into a folder on your SD7's storage. We made a file called MUSIC JPG for images and MUSIC PDF to keep files organized.
If you use Sibelius I can let you have the PDF print settings for best resolution, but honestly JPG is better quality and loads instantly - there is a little delay opening PDF files (2 or 3 seconds)
It works incredibly well.