Is there a way to change the font size of the pedal markings? It does not seem to use any of the fonts in the Font tab in Page Setup.
No, since it's one of the characters in NWCV15.ttf. Guess you could (using V1.70) hide the pedal mark, and insert a visual one using text (with one of the user fonts set to NWCV15).
Right, so it makes no sense to change the font. And it scales with the staff size. Unlike other staff notations, it does not have a standard size, and I would sometimes like it a little bigger. Well, its not very important.
On a couple occasions (using V1.55b) where I wanted virtual (unplayed) notes indicating alternative phrasing, I actually set up two of the User Fonts to different sizes of the NWCV15 native font; one for rests, and one for notes (using the grace note characters since the 'real' note stems are apparently drawn, not font-based). Add Boxmarks and Crescendo, and it pretty much uses up the user-definable fonts.