Debugger; draft mode

[Reilly]

I am ignorant of what is possible or available in Lilypond.

I am currently running 2.11.36 on a Mac PPC running OS 10.3.9. I write 
my code either directly into a Lilypond file or into TextEdit and then 
cut and paste.

(1) I am working on a symphony (22 staves) which takes more than 20 
minutes to compile and the time increases rapidly as I add more music 
to the score. I have developed a work around for "proofing" my input: I 
compile individual parts which take about 15 seconds. This is okay for 
checking note entry. But I also need to check part alignment 
vertically. Gosh, it is easy to get a measure off, especially when I 
rewrite an early section of the music. Would it be possible to add a  
\draft mode to Lilypond which would ignore markups, text, dynamics, and 
formatting and just do the music (4 bars to a line or something), so I 
can do a quick read-through of the score?  (Yes, I do know that 
Lilypond offers a feature to process only the most recent music --- 
this does not help me).

(2) I use TeXShop for my LaTeX. A superb program with an excellent 
debugger. When I process a LaTeX file, if the compiler encounters an 
error, it stops and offers me an option via a click button to "go to 
error." Usually the error precedes this location, but it does give me a 
start in debugging. I do not find the  Lilypond compiler window helpful 
--- in fact, I usually find it very confusing because the error 
messages are murshky-murshky to me. One misplace } can lead to 39 SCM 
error files messages. Perhaps, the limitation is in me?

Obliged,

Jeremiah