http://server6.uploadit.org/files/ChunkySoup-error.jpg) 
 I'm getting this problem in my map - there is supposed to be more grass texture in that hole, but instead it either goes reflective or transparent. Any idea what I might be doing wrong?  
 It looks just fine in the editor: 
http://server6.uploadit.org/files/ChunkySoup-noerror.jpg)
  
 
 
  
  
    Is your terrain made of detail brushes?
  A tutorial about detail brushes (
http://www.nibsworld.com/rtcw/tutorial_detail_and_hint_brushes_part1.shtml) 
 Another tutorial about detail brushes (
http://richdiesal.jedioutcastmaps.com/tutorials/gc102lsn3.html) 
 Edit: Terrain needs to be detail brushes, not structural. Apologies for my unclear posting.
  
 
  
  
    Nope, they were all structural. I checked by converting them all to structural again.
  
 
  
  
    Terrains should be detail. This looks like a VIS issue...I'd try checking for leaks first off.
  
 
  
  
    i had this problem i simple chenged the texture and it went away