One of the great new features of Archicad 16 is the Morph Tool. We are all learning new uses for the tool and one of the important features of the Morph Tool is the ability to align textures with greater precision. Check out this handy guide to see how to actually do this. It is a bit trickier than one would hope, but once you get the hang of it you’ll be a pro.
Here is the PDF:
Here are some great videos from Graphisoft:
This one is about changing the textures -
This one is about changing the direction of textures -
There is also a pretty good article on ArchicadWiki: