Retargeting Blender made skeleton to default UE4 skeleton

Hello!

I have been trying to retarget a Blender made skeleton to the default UE4 character. I am following the steps found on the Unreal wiki, but my character mesh always ends up being distorted way beyond an acceptable treshold (with limbs all over the place)

I am using Blender 2.73 and exporting the skeleton to UE4, and then retargeting it. Is there something I am missing in the process?