Mouse Buttons
Right button - drag object
Left button - Create object
Move mouse - Change size
If no object is drawn yet, Right Mouse Button cancels.
Keyboard Keys
< > - Rotate object
R / Shift+R - Change radius
PageUp/PageDown - Change radius
Home/End - Change #sides
Space - Toggles angle/size increment
Enter - Done
Esc or C - Cancel/Exit
+ - - Zoom Map size
Cursors - Move map
NOTE
If Snap-to-Grid is ON, the grid size determines vertex locations! However, if the length of a side is less than the grid size, it is ignored!