You can apply a map to several of the parameters on the Material Parameters rollout, including Occluded Amb[ient], Tip Color, Root Color, Hue Variation, Value Variation, Mutant Color, Mutant %, Specular, Glossiness, Self Shadow, and Geom[etry] Shadow.
To assign a map:
If the Slate Material Editor is open, you can drag from a map node's output socket, then drop onto this button
When you drop a map onto the map button, a dialog asks if you want the map to be a copy (independent) or an instance of the source map.