Start by hovering over the floor-plan point or line segment you wish to edit using the reticle (cross-hairs). Once on target, the item will turn red, indicating the point/line can be moved / edited / or labeled.
Additionally, you can elect to add a new point to any floor line segment and then hover over the new point or line segment to highlight.
While keeping the item highlighted (red), use the main middle white CAPTURE button, and press & hold to pick up the placed point. Move your device to re-position the point. Once satisfied, release CAPTURE button to lock in place.
Line segments can be modified in similar fashion. Hover over any floor segment. Press & hold CAPTURE button to pick up & release to place.
When adjusting points in 3D mode, an additional segment & point is automatically added to your room model, so the floor, wall, and ceiling move in unison. Points & line segments can be moved in both 2D & 3D.