[Zubersoft]

Is this happening with any song/piece you try it with, or does it seem to be specific to one in particular? If the issue is only happening with one song/piece, please long press that entry on the library screen, tap Share->Export as .msf and send the .msf to mike@zubersoft.com. To rule out any unusual issues, I'd like you to do the following:

1) Move or copy C:\Users\<your username>\AppData\Local\Packages\41730Zubersoft.MobileSheets_ys1c8ct2g6ypr\LocalState to another location.
2) Uninstall MobileSheets
3) Reinstall MobileSheets
4) Import a file and try entering the annotation editor with the default settings. See if it crashes. Close MobileSheets.
5) Move or copy the LocalState folder back to the original location and load MobileSheets. See if it crashes while annotating your songs.

This will help determine if the issue is specific to the library you are using or if it's happening even with a fresh installation.

Thanks,
Mike