What files were you changing ? I assume you know this, but I have seen cases where people make a backup of the XML files and when they rebuild the GUI, both the original and the updated copy are read, producing unpredictable results.
run this command:locate ui_custom.xmldo an ls -l for all of those files. Check the permissions on each
Use find then, there are copies of that file made to other folders. If one did not get updated, then you may see an issue like this.