Hey Jim,
in my posting above, I promised to make a photo of these threaded inserts that only come with Any Surface Leveling System (and unfortunately not with QCW Frame 
) as soon as I can, and until now it couldn’t – but look, now the manufacturer finally managed to provide a photo of it:
You see now why I always say, if anyone ever orders a QCW Frame, be sure to order the Any Surface Leveling System as well - not for the leveling feet, but just to be able to attach the QCW to a table the simple way – by bolts 