And here... here is a good site (and another less friendly one with much more info) with some fairly reliable information on real ship classes. Use a real ship as the basis for your vessel, and it becomes a lot easier to use SpringSharp in the early stages.
Use the 'Select All' and 'Copy' functions under the 'Edit' tab.
Then come here, 'Paste' the info into the text area- surrounding it with 'Quote' tabs never hurts, and then we can all see the design.