Two projects highlight some installation methodologies that, as a home owner, or designer, you might want to explore. In one case the home owner wanted a very rustic look and the roofer forgoed the traditional chalk lines to line up the tiles and went, instead for a more random "serpentine" look that immediately gives the roof and older look to it.
The second project highlights two aesthetic and installation choices - the solution, in the porticoes, of using the roof tile also as a ceiling tile, and also the choice or using mortar to fix the tiles instead of wire.