Quote - Ho hum ;-)

Shade Basic will probably not be much use as it doesn't seem to import the internal wave object group names properly. But Hexagon does seem to, so I might have a go with that... will try adjusting one sail if I can, to try to ascertain if this is definitely the problem.

Not used Blender much yet or Wings at all... would Wings be able to do this normals adjustment?

Many thanks for all the help :-)

If you have a normal coming out the back as well as the front, then two sided polys are definitely your problem :). Hex will work , as will Blender and it's a snap in Wings. What you'll need to do is select all the polygons on the back of the sail and delete them. Then export back out. This will not affect your material zones (so long as the sail is all one material zone) or your uvs....it just removes the uvs for those polys from the UV template.

Laurie