My abortive attempt at a blog has a tutorial on plaster-cast tiled roofs; the method is not perfect, but it looks OK on the table; it is really time consuming, though, and I won’t be doing it that way again.
My castle roof is made with corrugated cardboard; it is more complex because the concave roofs meet at a corner; again, it is not museum quality, but it looks OK on the table.
Thanks for the link religion, will check it out in detail.
Those are brave men knocking at our door. Let's go kill them!