There are no error messages referring to my own lilypond source files,
which makes me wonder what's going on here.
Your source is triggering an error in the library. Have you called
convert-ly -ed on your source in order to upgrade its syntax?
I understand that the lilypond-devel package is not intended to be
stable, and so bugs may appear. Is that what's happening here? If not,
I'm happy to try to create a small example that exposes this error.
First try convert-ly.
When I tried lilypond 2.19 on a different score, I had the above
error, but also some relating to my own .ly files. I guess there are
changes that I need to make to my source (even though I have `\version
"2.18.2"` in the source). Is that right? Is there a guide to these
changes?
<http://lilypond.org/doc/v2.19/Documentation/usage/invoking-convert_002dly.en.html>