New MuseScore update fails to open any new downladed files!

I just updated MuseScore at the iPad. I can open all my old files. Downloading a new file from my Dropbox did open the files correctly. They are also saved in the list. However when opening any new file from the list it says:
Mistake "Can't Open The Sheet Music"

Deleting previous files and reloading will create the same mistake. Opening the files from dropbox into MuseScore gives no problems.

I deleted the app. Restarted IOS and did load the app again. So I lost all files from the list (didn't make copy in iTunes) since the starts clean (except the 2 example files which are present and can be opened). Same problem after downloading my old files I cannot open any file from the list when downloaded again.

I'm stuck.

Rob