Seriously, in my undestanding thats not possible in demo. While I think the price of S1 licence is ridiculous low. With S1 you get layout editor and also very interesting new tracks and cars, all wich are worth much more than 12£
If someone know some cheats and hacks, I wonder how many will be interested to discuss them here.
Forgot to mention that with the price of S1 license you not only get things I listed in my first post, but also a great supporting community and friends. But if 12£ in your pocket is more important than all these things listed, then I just wish you good luck