I’ve seen a post about this before, but no answer was given. Importing an animation from blender and getting a bone transform is not from original error. Then the mesh with the animation is pointing straight up. And if played in level, it it points straight up. IDK!! I’m using 4.5 unreal and newest version of blender.
What exactly do you mean that it points straight up? (picture) 
-select the skeletal mesh + go to object-apply-scale/…
-I personally would recommend you to use blender 2.70 for skeletal meshes (you dont get so many problems)
-In this video you can see the process of blender to UE4: ?v=Ayp1lof0RJU
Here you can get some more information:
https://forums.unrealengine/showthread.php?55891-Animation-Exported-From-Blender-Appears-To-Be-Broken
https://forums.unrealengine/showthread.php?30827-Export-Rigged-Model-From-Blender-To-UE4
My bird mesh imports correctly and is facing x axis but in the next window for the animation, the bird is point up on z axis. And the animation will only play on z axis. So in the animation when I click to play animation, it rotates the mesh up and plays the anamation. Im using blender 2.7 and unreal 4.5. I didn’t have this problem with blender 2.6.