Flow along surface question

Hi there, I am trying to flow this mesh along a surface. I was able to flow it along the flat surface, but I wonder about the curved surface. Ideally I would flow it along the top of the curved surface and then the curved surface onto the flat cylindrical surface. The problem is that when I try to unroll the curved surface it is multiple surfaces and I am not sure how to deal with that or if it is even possible! Thanks in advance. Bark ring.3dm (18.4 MB)

Hello - ShrinkTrimmedSrf, then Explode and MergeSrf the object, which is a polysurface, not a surface.
(or better, make a clean new curve and extrude it…)

Then UnrollSrfUV and arrange the mesh on top of that, and FlowAlongSrf
Note in this case you can just Flow, not FlowAlongSrf from a line to the cross section curve of your curved object.