I regularly use XeLaTeX, and so have added this build profile:

    xelatex "%f"
    gnome-open "%e.pdf"

I hope that's right. I also use LilyPond, and wondered if it were possible to set up a build profile that would pipe the output of LilyPond-book into XeLaTeX while hiding all the mess in a hidden directory. I started by writing this:

    mkdir .xelytex
    lilypond-book -format=latex -pdf -o .xelytex "%f"
    xelatex -output-directory .. ".xelytex/%e.tex"
    gnome-open "%e.pdf"

I would use the extension .lytex for the input file. The mkdir command would not be a stopper so that the process would continue if the directory has already been created. LilyPond-book would create a lot of image files and the resulting .tex file and place them in the hidden directory. The question is how I now get XeLaTeX to process the .tex file in the hidden directory and output its PDF in the original directory. Any thoughts?