Move the pointer (cross mark on the circle in red) to the position of a vertex (corner) on the container top edge.
Click [OK] to set the position and display the pointer again.
Move the pointer to the next unconfigured vertex of the container and click [OK].
The position is set, and the pointer is displayed again.
Repeat steps 1 to 3 and select the position of the first vertex with the pointer at the end.
The container shape is set.
Up to 30 positions of the vertices can be set.