I have had this problem with LockToObject in the 3D window, render lights, now render material: If I add a render material I can’t disable it to go back to a normal render. There is no option to delete! I also set it to a material that I then deleted and saved, closed and reopened Blender ans its still there, won’t let me orphan the material! Please don’t tell me that my scene is trashed, please,
2.5 svn 29708 but this seems to happen with all older builds I have too.