Was interested to see what minecraft would look like with everything wingdingafied, but after the game started it wasn't affected. I looked in the log and found it applied Aharoni Bold instead.

[21:44:45] [Client thread/INFO]: [cubex2.ttfr.GlyphCache:setDefaultFont:205]: BetterFonts loading font "Wingdings"

[21:44:45] [Client thread/INFO]: [cubex2.ttfr.GlyphCache:lookupFont:268]: BetterFonts loading font "Aharoni Bold"

Is this just not supported due to all the goofiness it would cause?