It comes to me that the circle application presents novel challenges i overlooked in the last post. So here's a solution for positioning on a circular surface.
The problem is that a circular surface lacks a corner to align the texture against. Duh. Like that old ethnic joke.
My texture is 1x1 m.
My slab is 1x1. m.
The ends are bulged to .5m radius.
Easy to map to a node using the Align 3D command.
Then edit the slab to a circle by shifting nodes to the centerline between the nodes.
Now you have a circle on a face.
Dwight Atkinson