Thanks for responding!
I didn't realize that es_log.txt was an error log (again, I'm very foolishly new at this), and I've located the problem! The font in question needed to be a "TrueType font," and any other type like an OpenFont is apparently cause for error, which I didn't know. I cleaned out the folder and reset all default properties, and now it works like a dream!
You guys are the best! Thanks!