Would you mind explaining how you fixed it?
I know little about Kangaroo but quickly found differences in your data tree structures compared to @DanielPiker’s example. Your Crv list needed to be flattened and your Brep list needed to be flattened first, then grafted.

The starting positions (orientation) of your curves and breps don’t match Daniel’s example.
Custom Preview fails to show your mesh at all but enabling preview on the Mesh component shows something, albeit a little weird? Why?
OH! It’s because I’m using R5.
Connecting a Colour Swatch fixes that flaw.
FYI, leaving duplicate copies of code in a model is confusing. I looked at your first group and deleted the second. Oh rats, I just applied the same fixes to your second group and see better results, though still weird. Can you please explain your fix? Thanks.
P.S. I see you’re still working on it, good.