Trouble unwrapping a surface

hello I have modelled a closed surface but I am having trouble unwrapping it. I am clicking the unwrap button from the texture panel pick the surface seam that goes across the surface and click enter. It takes a couple of seconds but there are no info displayed on the texture panel. and when I open the uv editor I get the mesh as it would appear if I have chosen surface mapping instead

Is this some kind of bug? I tried with the Rhino 7 trial and it works fine.

Thanks for your input

Theo