Unfolding long repeats & rehearsal marks

[Jan Rosseel]

Hello, 

I'm trying to unfold long repeats (so we don;t have to jump back and forth in 
a SCORA score), and that works quite well. 

But there are a few things remaining. 

One of them are the rehearsal marks. When there is a \mark\default in a 
(long) repeat, the rehearsal marks will increment when unfolded. This is 
somehow logical, but is confusing when comparing with the non-unfolded 
"normal" score. 

Of course, I can do \mark "2" instead to force the counter to go back to 
where it should be. But then one has two "2"rehearsal marks in the unfolded 
score. 

So the question: would it be possible to have the rehearsal marks in unfolded 
repeats be numbered something like 2A and 2B, similar to the bar numbers for 
the alternatives that can be numbered with such suffixes? 

I assume a custom engraver would be needed for this? 

Thanks in advance, 

JanR