Reply to Installeation of s4

hey guys i just bought s4 off Guitar center used site. so i am very new i this. Tried to use installation cd that i got with the unit. Looks like i installed traktor pro soft for s4. i guess activ code was not active. that what i got in the message center. So i a trying to use demo just to see if s4 is working.... NO i see light on i was able to drom deno songs by buttons not responding. when i press play nothing is happening at all. i am no comuter wizz but i thought it should be plug n play. Please help me guys!