Shell cammand not work right?

I have surfaces hull boat, i want to make hull solid to print 3d. When i create solid by shell command, thickness = 3mm but not give solid hull. Rhino can not create solid.
i try command OffsetSurface, whith option make solid = yes, but result not right.
When i convert file to .igs and use solidwork command Shell->> give good result.
How to fix Rhino to give good result the same SolidWork Shell?v_hull_.3dm (1.2 MB)

rhinos thickening commands are not very sophisticated. shell was i believe a further development but still needs some obvious improvement. usually it leaves you with a bunch of surfaces which need a little rework.

here for example it did not manage to intersect the lower part of the bow. you can use the command intersect as seen in the image below and use ExtendCrvOnSrf to close the 2 curves then trim the lower part off.

then duplicate the keel curve and offset it an recreate the rest of the surfaces that way