To get swftools to embed all glyphs of a font for dynamic use (ordinarily it seems to only embed the ones it's statically sure will be used), do something like:
.font nitz "Nitz.ttf" glyphs="all"
I lucked out and discovered this post which described this feature about to be implemented
http://www.mail-archive.com/swftools-common@nongnu.org/msg01993.html
Also you need to set t.embedFonts to true, where t is the TextField object you care about. God, flash is such a pile.