Exporting animation in blender with 2.5x/2.6x/2.7x is notorious problematic. Here is a workflow that seems is working correct: Note that inclination angle (should be relative to X axis, logical)...for example 15 deg. Select the object you want to animate, and set cursor to selected. Add an empty and parent the object to the empty. No need for armatures/bones. Animate the object as is without the inclination. When finished. Rotate the empty to the inclination value and export.