I've started over from scratch setting up my table with the manual in hand.
All goes fine until I try to check column-to-column support adjustment.
With the arm indexed at 0 degrees and locked, the end of the arm can be lifted about 3/8 inch, and you can see the column shift within the column support.
It does NOT shift side-to-side and it is NOT shifting at the arm-to-column attachment point. Elevation resistance is normal.
To help visualize it, it's as if there's a missing lower stabilizing ring on the column, allowing the bottom of the column to shift front-to-back inside the the column support when the end of the arm is lifted by hand.
Is some vertical play normal? How much do you have?