[NTG-context] separating layout from content: section blocks?

To whom it may concern, I have a large document with several distinct pieces. Each piece has different layout requirements. I can setup the layout before each piece, but I would prefer to separate the layout from content. Currently what is the best way to do this? I have tried defining section blocks and then specifying the layout for the section blocks between \startsectionblockenvironment [mySectionBlock] and \stopsectionblockenvironment commands. I have also tried the project, product, component, environment structure from the manuals. I have not had success with either method. I would be very interested to know the approach taken by more experienced users. Thank you for your help. Sincerely, Andrew Crouse