Exporting or Creating Subset of .urd into a new .urd

[mellburg]

I am very impressed with the product. I would like to know the easiest way to create a new UR file from an existing one. For example, in my primary .urd, I have 300 articles broken down into logical groups (folders). If I need for someone to view only a single folder, is there a way to spit this out as a new .urd?

Thanks, Monica