The coordinates are correct. You set the colour first, then draw the quad. Keep in mind the coordinates are screen coordinates. They are not relative to the paster object. This threw me at first. Place it at 0,0 to experiment. You'll see what I mean.
+ System: On start of layout
-> Paster: Set quad color to rgba(33,66,200,100)
-> Paster: Draw Quad ((0,0),(100,0),(100,100),(0,100)) with blend Normal