[plt-scheme] Arbitrary TTF fonts in MrEd

As far as I understand it is impossible to use arbitrary (supplied with 
the application; without a system-wide installation) TTF fonts in MrEd?

I undertand that there were some supported platforms in the past which 
didn't support TTF fonts at all and that it is good to look as native as 
possible but I hope to achive some more consistent visual style on 
Win32, OS X and modern Linux in an industrial automation app in which I 
won't even use native widgets.

Would such a thing be difficult to add?

-- 
regards,
Jakub Piotr Cłapa