Rigid Body error while analysing frame with membrane

I am trying to analyse the frame structure as attached. When I try to analyse the model, I receive a “Rigid Body” error. I tried checking the connected parts and eigenvalue component. When I remove the membrane elements from the model, the error disappears. I suspect that this is because each membrane is connected to 2 beams (and not on all 4 edges if you look at the geometry closely). The membrane creates an intermediate node in the centre that I can’t seem to figure out how to eliminate.

I analysed the model on SAP2000 as well, and it seems to be running fine, but I can’t seem to make it work as a one-way spanning element on Karamba. Can someone help? Maybe there’s something else I’m overlooking?
Steel structure_Karamba_Wireframe.3dm (155.7 KB)

Generative Design_Obra_Alternate_Karamba.gh (74.8 KB)

your surfaces that you created do not touch all edge curves, and you are applying a load just on the mesh itself. You can also see that you have some gaps in your surfaces so if you close off the surfaces then the model should calculate.