Nets
Nets can contain any number of pages which can be any shape, not just rectangles. Well, currently only any flat sided shape. Bezier curve edges are not quite implemented yet. These are called nets, because faces can be explicitly linked to other faces, and different views can be unwrapped for convenience.
The usual use of Nets is to use a 3D mesh model as the basis to extract a net from. There is an OpenGL based 3D unwrapping interface, but I haven’t touched that code in a really long time, and it’s a bit clunky. In any case you can import an OFF file to use as a base polyhedron.
Another common use for Net imposition is for pamphlets, which are usually single sheets of paper folded in some simple ways, such as Gate Fold, Trifold, etc. A couple of interesting according folds can be folded into little books, in which case only one side is usually printed on, and inner pages end up having the fold along the edges.
