If you click on the edge of a wall then you will automatically get two markers at the centre of the length of the wall that will determine the wall thickness (as you have discovered).
Just click on the marker that you don't want and it will delete leaving just the one you require.
Or don't click on the edge of the wall, click on a node at the end of the wall and you will get just the one point.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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