I use an older laptop for my PT download to CP. I've been using the 9 pin serial port to connect the download cradle. That connection has, for some reason, failed. I have positively identified the serial as culprit. The laptop does have one usb port. Could I use a usb to serial cable to get up and running again? Would I need any computer savy beyond plug and play? (I'm a Mac guy and the PC is freakin' me out)