Before I can help you with the touchscreen not working, I need more information. What is the model number of the board? What is the OS Windows/MAC/Linux of the computer? What ActivDriver do you have installed on this computer? Have you tried a different USB cable going from your computer to the board? Have you tried a working computer from another board on this board? Do you get the same results?
soon as we have this information we will be able to advise how to proceed next.