[itsme]

Motivated by https://zubersoft.com/mobilesheets/forum...12075.html I investigated ABC handling (MobileSheets 3.9.3 on Win10)
I documented most of the steps as that might become a frequent workflow for me as soon as ABC integration in MobileSheets works  fine.

I started with an existing score in MuseScore 3.6.2 and used the plugin ABCImpExp V1.1 to create an ABC file.
Both FreudeSchoenerGoetterfunken_ABCImpExp_ANSI.abc and FreudeSchoenerGoetterfunken_ABCImpExp_UTF8.abc look fine in EasyABC and could be imported into MobileSheets without errors. 
When I try to open any of them in MobileSheets it shows the endless blue circle as reported and is not displayed. So the encoding is not (no more) the cause of that issue.

Just renaming the file to FreudeSchoenerGoetterfunken_ABCImpExp_1.pro did not help. FreudeSchoenerGoetterfunken_ABCImpExp_1.pro can be imported and  MobileSheets displays the ABC code as text - not unexpected.

In FreudeSchoenerGoetterfunken_ABCImpExp_2.pro I just added {start_of_abc} and {end_of_abc} and it is imported and displayed in MobileSheets correctly!
This is a hint that nothing's wrong with the ABC syntax, assuming MobileSheets uses the same ABC package for ABC files as for ABC code that is embedded into a ChordPro file
It might be a feasable workaround for users that want to use "ABC only" files immediately, already with the released MobileSheets 3.9.3.
   

[itsme]

In FreudeSchoenerGoetterfunken_ABCImpExp_3.pro I added some $ characters to split the score into showing 4 measures per line.
   

My main usage of ABC will probably be ABC notation integrated into ChordPro files, using ChordPro and/or MobileSheets' ChordPro features for title, subtitle, lyrics and all the other stuff.
So I added those elements in ChordPro syntax and removed the according entries from the ABC section.
FreudeSchoenerGoetterfunken_1_ABC.pro looks already pretty good in MobileSheets.
   
I had to add the ChordPro chord [F] before the ABC section to tell MobileSheets what key we're in. This is not only used to fill the "keys" field in the database during import, but also required as the starting key for transposing. MobileSheets could have detected the key from K:F in the ABC section. Open question: what to do when the existing ChordPro method (first chord / last chord) and ABC tell a different key.
Btw: at first glance transposing works correctly.
After import Lyric Size is set to 22 which is too small compared the width of the ABC part. Setting Lyric Size manually to 32 uses the full width of the page. "Auto-Size Font" sets it again to 22.
Off topic: I have to scroll every time to reach the "Auto-Size Font" button even in case the screen would be big enough for a higher "Text Display Settings" window.
Off topic 2: On Win 10 it's very convenient that the score is still visible in the background and shows my changes in the Text Display Settings window immediately. On Android the score is hidden behind the settings window - less convenient.
   

[itsme]

Looking at FreudeSchoenerGoetterfunken_1_ABC.pro with ChordPro 6.060 shows significant differences.
       

In FreudeSchoenerGoetterfunken_2_ABC.pro I added %%pagescale to get back to 4 measures per line and %%stretchlast 1 to make the last line the same width as the others.
In MobileSheets FreudeSchoenerGoetterfunken_2_ABC.pro there's no change. The missing lines in the score as marked have been there before. It's not predictable if and where that occurs. Maybe the lines are just not thick enough so that they sometimes disappear depending on the screen resolution and the position on the screen.
       

[itsme]

FreudeSchoenerGoetterfunken_ABC.pro should be my final version. I added chords to the second verse and use a custom config to get my preferred appearance.
   

The same source file in MobileSheets already looks pretty good, Lyric Size = 32, Chord Size = 32 to use the full page width and look as similar to the ChordPro PDF as currently possible.
   
Transposing in MobileSheets has an important advantage compared to transposing in the ChordPro Reference UI: Mobile Sheets allows chosing between transposing up or down whereas ChordPro always transposes up.
On the other hand Chord Localization doesn't work yet for the ABC section in MobileSheets, in ChordPro chord localization (transcoding) works fine (I always use Source=default, Display=Scandinavian and that's the only combination that I test usually)
   

My wishlist of open issues to be fixed for now:
- correct chord localization
- allow bigger chords and bigger lyrics in the ABC section
- an optional handwritten font for chords, preferably MuseJazzText
- the same font for the lyrics & chords section and the ABC section
- Auto-Size Font corrected so that that width of the lyrics & chords section matches the width of the ABC section
- more font formatting options as discussed in other threads