Just to clarify, when you say 'guide lines', you mean the orange guide lines and not the blue snap guides - they can't be moved.
A move spot should appear on an orange guide line so long as you touch it with the mouse.
I recall a post related to this, a quick search turns this up - does anything here help?
https://archicad-talk.graphisoft.com/viewtopic.php?f=20&t=71837&p=321626&hilit=guide+line+move#p3216...
Barry.
One of the forum moderators.
Versions 6.5 to 27
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