Help with strange issues with skeletal mesh.

Okay so I just make a Giganotosaurus TLC in blender and rigify, sadly I get a number of issues when exportion the skeletal mesh and bones into the kit. First of all for some reasons the mesh floats in the preview and the bone sockets are huge, I have set the model to export with the right scale settings but that has no effect. Th second issue is even worse, when I test the dinosaurs half of it´s body is underground having this weird rotation.

I´m really desesperate to fix this issues as I have spent a good amount of time creating thi mesh and animations.