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It looks like you have your "Delta" unchecked on your coordinate XY toolbox.
I wouldn't have expected the Delta settings to have an impact. I have however experienced some strange stretching behaviour in 4000 UKI with CP beams in 3D that don't seem dissimilar to the screen shot. A small movement to make an adjustment sends the projected end of the beam shooting off the edge of the screen. Once a suitable node or measurement is applied the beam is as expected. Unfortunately this sometimes means now having to zoom in to connect to a suitable point. It feels like the screen "scale" and original reference point have become irrelevant whilst the program hunts around for a new connection.