problem with stronghold 2

I need a lot of help here guys. I downloaded stronghold 2 and then used the auto-updater to patch it to version 1.3.1. problem is i am unable to use the crack. it's an image file. Intructions tell me to burn the image file as "normal cd". and then set rmps emulation on. But when i try using alcohol to burn the image, it does not work. It keeps asking me to insert a cd/dvd into the recorder.