I think the format could be pretty easy.

But for the chord grid, it should be as easy as the BIAB chord grid (I would use an underscore to distinguish the first two beats from the 3rd and 4th beats):

|| - continue playing the last chord entered for this bar
|C| - C chord for whole bar
|D_G| - D chord for first two beats, G chord for 3rd and 4th beats
|C,F_ G| - C on first beat, F on second beat, G on 3rd beat
|C,F_,G| - C on first beat, F on second beat, G on 4th beat
|C_,G| - C on first beat, G on 4th beat
|,C_,G| - C on second beat, G on 4th beat
|_G| - continue playing last chord entered for first two beats, G chord on 3rd and 4th beats

From there, you should be able to include standard BIAB embellishments - pushes (^ and ^^), as well as rests (.), shots (..), and holds (...), as well as the different types of supported chords (C7, Gsus, Bdim, etc.)

You could have a simple header that might be something like:

Title
Style (would have to be spelled properly, or maybe the style file name)
Tempo
Start,End,Repeats
etc.

One Man Band has a similar facility for entering this type of information.

John

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