Oops, I realize I forgot to mention that I didn't have defoma installed, so I used apt-get to install this, as well as x-ttcidfont-conf. I also added /var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType and /var/lib/defoma/x-ttcidfont-conf.d/dirs/CID to my FontPath as mentioned by x-ttcidfont-conf as well as by Alan's message. I did all this before changing and rerunning the update-ms-fonts scripts, after which everything worked again.