How to write UserDictionary into ModelObject then using ContentCache?

As the title suggests, I need to write custom metadata to each object’s UserDictionary in C#, and then bake those objects into the Rhino document via the component ContentCache. I like the manipulation logic of the component ContentCache, but I can not find a way to save my custom list of metadata.

Since you bake the model objects with Content Cache, why don’t you add the metadata with the native User Text component?

I mainly hold an idea to store a plane instead of string to improve performance. And can save a series attributes in a dictionary for well organization.

Which key value types does your dictionary have?