SuperPaint - to draw dotted lines - choose one of the larger line widths, then choose one of the smaller dots as a brush shape. Use the Paintbrush to put a dot on the screen, go to the Options menu and choose Grid & Rulers. Check the box Grid Snap On and adjust the numbers in the Grid Spacing Box.
(0.05 will give you dots further apart than 0.10.) Lasso the dot, and drag it while holding down the COMMAND and option keys.