D - Activate addon. Creates a grid on the closest face under the mouse. If no face is found, it creates the grid on the 3d cursor location (snapped to world space).
While the addon is active:
D - Create the grid on the face under the mouse. If face normal has a different axis than before, drawn boxes are erased. If the face normal is not World Axis aligned, works the same as 'F'.
F - Force the grid on the face under the mouse, and use the closest edge as the grid basis (you can check the "Force to face" in the T-Panel to make this the default behaviour when pressing 'D').
F (TWICE) - Same as before, but uses the closest edge length as the grid size. Pressing F again after this will revert the grid back.
LMB - Two click method for creating a box. You can pan and move around with this method.
LMB (HOLD) - Drag and release method for creating a box
ALT + LMB - Create the first vertext of an ngon. Subsequent LMB (without ALT) clicks then add vertices to the ngon.
SHIFT (HOLD) - Activate the 0.1 step grid (works with all of the above)
C - Delete the last box, or ngon vertex.
S - Snap to grid On/Off (also in T-Panel)
CTRL + LMB + DRAG MOUSE LEFT OR RIGHT - Adjust the extrude amount (+ SHIFT to adjust by 0.1)
E - Flip the extrude direction
0 - Set extrude amount to 0
CTRL + MOUSE WHEEL - Move the grid along its normal (+ SHIFT to move by 0.1)
PAGE UP, PAGE DOWN - Move the grid along its normal (+ SHIFT to move by 0.1)
X, Y, Z - Change the grid axis
+ - Increase grid size
- - Decrease grid size
SPACE - Finish
ESC - Cancel