Re: insertions ?

[Mats Bengtsson]

> hello,
> 
> I'd like to know if it is possible to insert some
> comment on a staff like "Moderato" or something
> else, or letters like "A"

Certainly! If you want to put text above a note head, 
read in the reference manual on Text scripts (in the
chapter on Ornaments). If you want to set marks 
above the bar lines, read the section on Rehearsal
marks (in "Writing parts"). 

If want a quick overview of many of the features
in Lilypond, take a look at the "Regression Test"
(linked at Documentation - other... at www.lilypond.org).

   /Mats