Hi Gordon, so the reason why Network is not working on your curves there is that your layout does not form a regular grid pattern which Network needs.

Part of a regular grid is that all of the curves in one of the 2 U/V sets should either all be closed or all be open.

In your case you have closed curves here:



And then an open curve here:



So because some are closed and some are open it won't work for all those curves to belong to the same direction set.

With this curve structure you would want it to be configured into pieces like this:





With it set up like that you would be able to use Network for one half of the hull.

However it's going to be messy because there is too large of a gap in this area:





There are some links to some previous discussion threads on ship hulls here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=3814.1

- Michael