have you tried replacing the styles defined in the fckstyles.xml file with the style that is in your .css file? the styles you want to show up in the styles list must be defined both in the .xml file and in your .css file. in this case you just have one class, so there would be just one style defined in the .xml file. hope this helps
RE: Load style sheet?
RE: Load style sheet?
This really should be indicated in the documentation, which is quite poor sadly.