[Therion] Projected Elevation Output

I am trying to draw a 90 degree elevation. All seems well but the PDF output shows the topo survey as shown in the .th2 file background and not the walls etc that I have drawn. I can't find any reference to this problem in the available information or archives and after 2 hours have decided to go for beer. I'm obviously missing something anyone got any ideas. The extended elevation works perfectly. Nick.