Ok. Thanks, just wanted to make sure.
Aaron is stating the same error, XGUIinit hook failure in the actual release thread of XGUI.
Keep an eye out there. Perhaps Stick will be able to stop by during his winter break and hunt down the issue.
EDIT - OH. Wait. Your's is an actual ULib error (that would also affect most other mods which watch for UCL authorization.
Not sure. Made sure to update your servers cache, simple stuff etc?
Maybe Megiddo can spot it (but, he's busy during his winter break too)