Mac OS X board design software aku ?

Been working with aku shaper on my Mac trying to sort out some prone paddleboard designs. I’m having trouble with the program not allowing me to work with certain thicknesses … Is there a way to shape something >5.5 inches thick or whatever the limit is? Also working on the concave well on the deck of these boards… Is there a way to do this? 

Seen pictures of Shape 3d designs that appear to allow these features … Any advice with aku or other software for the Mac? 

Use BoardCAD

It’s opensource http://www.boardcad.com/news.php