Mold Split - Block Sizes

Hi Everyone, I am at the Tooling Split stage of a mould design, having created the Parting Line and Parting Surface, all looking good so far. However when I enter the Block Sizes of 100mm and 70mm respectively, it projects these sizes from the Part Origin, not the Parting Surface. The Part (imported) has it's Origin 2.012mm above the Parting Surface (inside the Cavity) so I end up with a Core block size of 67.988mm and a Cavity of 102.012mm. I have no interlock checked and have entered "Parting Surface 1" in the "Parting Surface" box at the bottom. I know I can just get around this by fiddling my Block Sizes to take account of the 2.012 offset but this cannot be right..............can it please?

Thanks,

Roger

SolidworksPlastics And Mold Design