Alright, I think I found the cause of the "blank font" issues (at least on the KT, and for this application, that is).
Simply looking at the output of "showlog -f" revealed this:
Code:
[!]120302:202704 root: (process:6129): Pango-WARNING **: failed to create cairo scaled font, expect ugly output. the offending font is 'Helvetica Medium 32'
[!]120302:202704 root: (process:6129): Pango-WARNING **: font_face status is: <unknown error status>
[!]120302:202704 root: (process:6129): Pango-WARNING **: scaled_font status is: out of memory
[!]120302:202704 root: (process:6129): Pango-WARNING **: failed to create cairo scaled font, expect ugly output. the offending font is 'Caecilia Regular, 36'
[!]120302:202704 root: (process:6129): Pango-WARNING **: font_face status is: out of memory
[!]120302:202704 root: (process:6129): Pango-WARNING **: scaled_font status is: out of memory
This coincides exactly with the fonts/sizes that are displayed "blank". I'm thinking about how this could be solved, but if anyone has a clue... *please* post here.