What do you mean by "fix"?
GTK3 is a fast-moving target which still lacked certain features as of
several months ago; as a result TDE doesn't have full theming support for
it yet. As soon as GTK3 development settles down enough I'll update the
theme engine and fix some of the remaining (irritating) bugs.
The fonts are blocky looking. The GTK2 fonts look great once a gtkrc file is edited ---
smooth, fine, aliased, etc., but not the GTK3 fonts. The GTK3 fonts look great in GTK
based environments such as MATE, GNOME, Cinnamon.
Darrell