Unexpected Error when in Picture lab
I am using Bryce 7.1 Pro and exported an HDRI image into a Spherical Map. I then go into my picture editing program, GIMP 2.8, and modify the BMP (mirror it and then offset it to match the HDRI image). I go back into Bryce and create a new Bryce default sphere. I go into the materials for the sphere and switch on a Picture texture. When I try to use the modified BMP I get an "Unexpected error (generic failure)" message. Now if I use the unmodified BMP or a modified JPG file I have no trouble.
My question is, is this an issue with modifying the BMP in GIMP 2.8 or is it an issue with Bryce?