I am trying to hide some columns from view in the DIP, but allow users to change them in the properties panel for the document. I am trying to associate 3 base content types for attaching different document templates with some custom columns. A lot of content types with additional columns with inherit from these in the future, so I don't want to lock down the DIP.
I've tried hiding the columns, but then they don't get included, for some reason, when I try to save it as a document template and re-create the library from that.