Add control to selection

Select control while holding Ctrl down
(if the control has already been selected, it becomes a Master)
Select control with Shift key pressed
(if the control has already been selected, it is deselected)

Invert grid use

Drag control while holding Alt down

Drag control strictly vertically/horizontally

Drag control while holding Shift and Alt keys down

Drag control strictly vertically/horizontally and copy

Drag control while holding Ctrl, Shift, and Alt keys down

Copy Leveling Line

Drag leveling line while holding Ctrl key down

Move leveling line without docked controls

Drag leveling line while holding Shift down

Resize form and move docked controls

Drag form edge while holding Ctrl key down

Copy control

Drag control while holding Ctrl key down