Looked at the logs for the first failed build, and found this:

(cd debian-tei-roma; debclean; debuild -i.svn -I.svn -uc -us)
/bin/sh: debclean: not found
/bin/sh: debuild: not found

These are in the package devscripts, so sudo apt-get install devscripts. I'll try the build again.

Looking at the stylesheet failure, we're missing xsltproc, so sudo apt-get install xsltproc. Then trying again, noticed I need debhelper, so sudo apt-get install debhelper.