Of course you won't offer a guess.

Your abilities as a programmer are bar none,

Your abilities in dealing with a proven problem are either "I don't use that mod with it" or "it should not being doing that".

Thank you Captain Obvious.

After several successful orders on the site this evening, I went in and (again) changed the jscript_square.php to jscript_goofy.php All OPC orders failed with a token error.

Changed it back and orders processed completely.

I had similar problems in 1.5.7d with removed (not uninstalled) files for the old square or I would NEVER have thought to try the jscript_square.php insertion.

Sadly, I expected the denigration and washing of hands but, maybe it just might help someone in the same situation.