A bit more explanation: those command you see in the Pet Palette (the little Palette that offers those editing commands) are two types:
1. the top row are polygon editing commands - the modify a segment or node of a polygon. (They can also contain other commands that modify the geometry of the element).
2. the bottom row are element editing commands - they affect the whole element: move, rotate, etc. it
2 or more selected Walls are considered by ARCHICAD to be a polygon (on which polygon-editing commands can be performed) only if they form a continuous polygon (which is not true in your case, but is true in the Tutorial).
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