[maintech]

As previously noted I finally got my Korg PA600 to talk to the tablet and Mobilesheets with the result that selecting a song on the tablet selected the musical settings for that song title on the keyboard,  and everything seems hunky-dory, until something removes the stored Korg song number in Mobilesheets. I have applied about half of the 385 Korg songbook numbers (190 at last count) and something seems to have lost or 'deleted' a number of them. What is happening? I use the same procedure each time:
 
1. Call up the song on Mobilesheets and select it for editing.
2. Select the Midi page.
3. Display the Korg songbook entry on the keyboard.
4. Assign a song number to the Korg entry and save it on 'Edit page 2'.
5. Press the 'Plus' sign on the Midi page to bring up the midi value choices.
6. Select 'Number.'
7. Enter number and confirm in box and on page.
8. Select 'send and receive' tabs so both tablet and keyboard talk to each other.
9. Select 'okay' (top right corner of page) to save.
10. Load song to check, both ways (as per tab set #8.)

If I return to any song during that session, the number is still there, but if I shut the tablet down and return later, some songs have no number, and I need to re-apply the song number.
Would backing up the data solve this? 
Has anyone had similar issues?