Hello, I am Brazilian and I'm using Google translator, excuse the bad English. I downloaded the demo version 8.0.3 and when I edit the four points of the runway surface, there appears the option to add a new item, I can only edit the entire surface of the track, has the "-" button but the button does not appear "+ "as explained in the video on the site of BTB. The other options are working perfectly, but has built a track can not edit the surface curves for example. I downloaded version 8.0.0 and the same thing is happening. I use Windows XP.