The changes list introduces the concept of Structural Shells:
http://aurora2.pentarch.org/index.php?topic=8495.msg106758#msg106758But the design window says
"This design is classed as a Space Station for construction purposes"
Given that there is a Hull Type on the Class Design screen called 'Space Station' but that this does
not require the design to use the structural shell rules, we now have the situation that a design can end up:
1 -- A Space Station (by hull type) but not a structural shell and therefore not "a Space Station for construction purposes"
2 -- Not a space station (by hull type) but indeed a Structural Shell (by checkbox) and therefore "a Space Station for construction purposes"
3 --
Both Space Station (by hull type) and a Structural Shell (by checkbox) and therfore "a Space Station for construction purposes"
and of course, 4 -- Neither a space station nor a structural shell; in other words, a regular ship.