The error of not finding "..." (anything) that repeats to infinity has to do with the AUGUST 26, 2003 PATCH
They added WindowPieces06.tga
These are the 1-10 buttons you see on the default UI behind the hotbutton window.
Now any UI built before Aug 26th didnt have any use/need of these two peices soo it did not call for them in the Animation file.
Not Untill now
The Melee Ablities windows uses these two items. BUT if you have not added them to your Animations file from the patch (because most people don't patch thier UI till it breaks) then you will get the error:
Warning: file UIFiles\Your-UI\ not found in directory UIFiles\Your-UI\
where no specific file is listed.
Please check the Aug 26th patch fixes
posted by Cairenn and add the two lines for WindowPieces06.tga
and this error will go away