Are you sure? I'm at work right now and cant try it. I know the number keys on top takes you inside the cab but i was thinking the number keys on the right hand side (number pad) turns on the beacon. I will try it when i get home in 3 hours.
Make sure you have all the new dependencies. The demonstrator pack has the old dependencies in the pack that will do that if you overwrite the newer dependencies.
there was an old dependency for the beacon that was for some reason invisible. the beacon works fine you just couldnt see it. there should be an update on the DLS.