c2s are Click 2 Stitch files and can be converted using Floriani's Embroidery software. I believe it's a fully functioning trial version so you could convert all your c2s files during the trial period and then not go on to purchase it if you don't find it useful in any other way. hth :) xXx
Something comes to mind that you have to buy their software.Maybe someone else knows more what to do. good luck