I am able to create a shadow map (without actually having a shadowmap, but generating it rather), but I didn't put the time into figuring out how to implement a detail map additionally. I'd have to add an additional pass, and then dest/src blending.

EDIT: Actually, just adding the standard material diffuse to a current terrain may work - if you don't add an actual effect="", the detail map should stick. If not, I'll write up a simple detailmap shader+diffuse... (If time allows me to of course).