Blender animation export to UE mesh becomes altered

[AncientLawAvonin]

Hey guys i need some help,

So ive imported an animation from blender to UE4, the basic skeleton has moved across fine with no animation but the moment i export the same skeleton with an animation, the mesh when loaded in becomes altered, shown below in the image the one on the left is the normal one and the right is the animated one, the animation is a simple raise of the arms, so no face bones are used, any ideas to why? i get no errors when importing.

[AncientLawAvonin]

Ok so no-one answered, but after a day or so of working on it essentially what this is, is a scaling issue, if this is something you encounter please be aware that to properly scale the bones and mesh