This has been discussed to some length in the newsgroup (creating trimmed BReps from surface and (u,v) trim coordinates), but I would like to know if there are some examples for RhinoCommon to create a trimmed BRep from scratch.
For Rhino_DotNet there are examples to do this at http://en.wiki.mcneel.com/content/upload/files/BrepSamples_net.zip
I have tried to follow these samples and reproduce them in RhinoCommon, but so far no luck. I get stuck when setting vertex indices on loops or edges IIRC.
A similar example in RhinoCommon, creating a planar face with a hole, and a trimmed face would be much appreciated.