Before troubleshooting any farther, remove/uninstall your ULX/ULib /addons and /data folders.
Then, go to
https://github.com/Nayruden/Ulysses/ and download the zip of our latest code. (our "release" is ancient in "GMod updates breaks us so we have to update ours" terms).
Though there are many things in the zip, only worry about the ULib and ULX folders; re-upload them to your server /addons
Make sure you're superadmin as you would have before.
When in XGUI, as of THIS post, your XGUI panel version should read v14.8.9