Surface Loft Oddities

Hi everyone, relatively new to SolidWorks so please forgive me for my ineptitude,

I have created a shape (attached below as the tray), which will be the basis of my design. This was created with four of surface lofts. I am now attempting to create a case like structure (attached below as Shellv1) for it, with the same overall shape, but with a 0.5mm clearance between it and the new structure. This shellv1 is meant to have a 3mm thick wall. In the Shellv1 file I have attempted to create the new boundaries by using offsets of the original tray sketches, but this has led to spaces being created between the new lines, resulting in me being unable to create surface lofts excluding one. The loft which I am able to make is one of the inner lofts. I am unsure how to get everything to fit correctly into place with the other lofts.

Thanks for reading,

Dylan

SolidworksParts And Features