According to the wiki, all you need to do to build a custom library is included diylc.jar into your project and drop the resulting jar into the 'library' directory. This does not work for two reasons:
1) getComponentTypes in org.diylc.presenter is hardcoded to search only for 'org.diylc.components'
2) The project does not try to load any jar files in the libraries directory.
It seems the code was here, but has been commented out. I am working around this for now but obviously this makes distributing my library impossible, and I do not understand enough java yet to correct this properly.