1) I am not able to use mixed mode style for the Piano
pedalSustainStyle below . Maybe i am missing an engraver ???
I leave this question to others who are more experienced with
piano music.
2) i don't know how to (or is it possible ?) to render a double
beam chord like in measure five (bass voice c.f old score). This
is indispensible if we have a cluster like chord with c cis d dis
in the same register
You mean double stem chord? Unfortunately, that's not supported
for the moment.
3) how can i put a slash for a grouped gracenotes (accaciatura like)
You mean a slash through the beams? I might be wrong, but
the best solution might be to draw it with embedded postscript
code or something like that.
4) how can i put brackets around a chord like in measure 14 in
old score ?
Hmm, the left bracket is easy, see the section on Arpeggio
in the manual. I'm not sure about the best way to get the
pair of brackets, though.
/Mats