Hi Dave, for this one it looks like you need an "extrude with draft angle" or "tapered extrude" type command, which MoI does not currently have.

As a substitute, you can try using offset on the curve, and then positioning the curve and the offset version at different z heights and then lofting between them, that is described some more in this post: http://moi3d.com/forum/index.php?webtag=MOI&msg=941.5

However, I don't really think that MoI is suited for this kind of design, stuff that looks more like relief work will probably be much better done in more specialized software for that kind of shapes like something like ArtCAM for instance.

Actually your bird design kind of falls into a similar area - it will be tough to get the kind of slightly raised bubbly shape that you are looking for in MoI, doing something like one single sweep along a complex path curve like the trailing edge of your wing creates a super super dense and complicated surface that sort of torques and wiggles around a lot, something that is more specialized for relief work will create that kind of raised shape probably a lot better.

- Michael