Bill
this can be done with the bits that come with the cw. It will just be more work with the software. A 1/4" bit would be much better for the 1/4x1/4dado even though they don't show a 1/4" bit in the software. Just get one the same length as the 1/8" bit. Turn the board over and draw a straight line where you want your dado. or if you do use the 1/8" bit draw two lines 1/8" apart. It goes by the center of the bit As for the 3/4x 3/8 you can draw a rectangle with a carve region I think and select the 1/8" bit or again draw several staight lines. mybe try it on scrap first.
1.187 Custom Woodworking for more than 40-years