Carsten, one of BoardMod's popular YaBB mod writers, is the first to release a mod from beta to final!  His CSS Button mod for YaBB 2.2 is now on BoardMod's FINAL Mods for YaBB 2.2 board.  Here are Carsten's comments:

Ever wanted to add a new set of graphic buttons to your YaBB but gave up because it was to much trouble making more than 60 different graphics?

With this mod you'll get the job done by making only 2 - yes TWO - small graphics!!! One left part 20x10 px and one right part 260x20 px in .png or .gif format. Give them the same name except for the last part which must be '_left' and '_right'. Place them directly in the 'yabbfiles/Buttons' folder and - Voila - they will appear in the Style Sheet wysiwyg editor for you to add to your templates.