Little bit rusty. I want to take these discs, which have some thickness, and attach them the wavy surface. I also want the discs to deform to the surface. I have been trying to use Flow along Surface but they do not attach. Maybe another tool would be better.
FlowSrf should work… What are you using for a base surface under the discs?
Remember, this is a mapping operation. You are mapping your discs from one “surface space” to another. If you have a rectangular planar surface under your discs (that they are sitting on) that will be mapped to the curvy surface, and the discs will sit - or rather be draped Dali-style - onto the curvy surface. The base surface as well as the flow-to surface should be untrimmed.
You may want to sink the discs very slightly into the base surface so that when the Flow is done, you can more reliably BooleanUnion to the target surface. It might not work if they are just sitting on the surface.