Maximum Coordinate + rotation

[[Se...]]

Hi all,

Created a program to measure the diameters of individual fins in a bank of four. Using auto line to scan up the bank, then use Maximum Coordinate (Y in this case) to find the greatest radial values.
When I rotate these scans around the the part, the scans work fine, but the Maximum Coordinate results seem to NOT follow the rotation, despite recalling the same alignments as the scans, hence as it works around the part, Y decreases and X increases, until at 90 deg and X has become the original radial value, etc.

A colleague has created a very similar program using the same method, and the Maximum Coordinate follows the rotation, Y is always the radial value and X is always virtually 0!

What am I doing wrong?