I've made a custom shape node from modifiing apiMeshShape example Maya provides. I made it as a shape with double indexed components of type MFn::kSurfaceCVComponent. I can manipulate the shape with cnotext tool successfully. All the components in my shape are all represented as xxxxxx.cv[uid][vid]. Everything works great so far. However, when I select some components and press "CVs (click to show)" in Channel Box / Layer Editor panel, there is nothing shown in the table. Only an empty table is displayed. Is there somthing I miss for double-indexed components?

Any idea appreciated. Thanks.