I've downloaded and opened the 'ortho grand canyon folder' twice. XP11.51 loading stops with a window stating that 'can't find 'terrain/texture 102128_48096_NAIP18.dds'. My highest #.dds file is '102080_48976_NAIP18.dds' which suggests there are quite a few missing. As it stands files for TERRAIN are 11,080 while those for TEXTURES are 473. Both downloads showed identical numbers - any thoughts?