it is under SkinInfo tag only?! (at least the Schema says that it would be like
code:
<SkinInfo>
...
<Fonts>
<Font>
<File>....ttf</File>
</Font>
</SkinInfo>
I'm not sure if it is <Font><File>....ttf</File></Font>, or <Font>....ttf</Font>, try both, but check if the only tag above it is SkinInfo!