Aaargh! No textures on clouds or autogen trees

Hello fellow flightsimmer,Maybe someone already had this problem and is able to help me:http://forums.avsim.net/user_files/107640.jpgAs you can see in the picture above my clouds and trees are "texture-free". This happens as soons as I climb above (approximately) 7000 to 8000 feet. Whilst I am on the ground or only two- or threethousand feet high everything looks fine.My specs:AMD Athlon XP 2800+512MB RAMATI Radeon 9700 mobile (64MB VRAM)Windows XP ProFS9.1 (+size reduced cloud and autogen textures)ActiveSky 2004.5 Build 174Robert Lechner