I have the same problem with lyx-1.3.1-1rh8-qt.i386.rpm as Johan Marc and although I wouldn't know where to find latex-ttf-fonts or where to install them if I did, I think we are talking about display fonts here and I can't find anything wrong with those. Unfortunately I can't compare with the result from building 1.3.1 from sources because that fails in so many ways that I can't even begin to describe them all. (However, several have appeared on this list and seem to be known issues with qt which are not resolved.)
I bet the lyx-1.3.1-1rh8-qt.i386.rpm problem is not a big deal and somebody can tell me how to fix up the display fonts. Steve Gregory
