Can I use the Sulky 12 wt. or 30 wt. Cotton for computerized embroidery?

You can, and there are more and more designs digitized for the heavier 30 wt. and 12 wt. Cotton Thread, especially with the popularity of Redwork and the many designs now available for that. HOWEVER, if the design is not specifically digitized for 30 wt. and 12 wt. Cotton thread, you may need to enlarge it to accommodate the thickness of the thread. It just depends on the digitizing. Many of the outline designs will work fine without enlarging, but you need to do a test sample first. (See the tension recommendation below.) Almost any filled-in design that is not digitized for 30 wt. and 12 wt. Cotton will need to be enlarged.