Help : Rotating Objects in world editor

Sorry if this question has already been answered- i tried looking for it on the forums. How exactly do i rotate an object while in the world editor? creator or inspector. I tried modifying the rotation '1 0 0 0' while in inspector but when i apply it it defaults back to 1000. I set it at like 0 1 0 0. Im putting a cave together and need to rotate the objects 90* .. should be easy - thanks for your help.