When you export data from TBC to DWG, the Plan View data is exported to AutoCAD Model Space and the Sheet View Data is exported to AutoCAD Paper Space if selected in Project Explorer as Plan Sets, Sheet Sets, Sheets or to AutoCAD Model Space if selected graphically as objects.
However when exporting from the Sheet View you need to select data from the Project Explorer (Plan Sets, Sheet Sets and Sheets) to send them to the DWG file as Paper Space.
A Dynaview is transferred to AutoCAD as a Viewport.
If you select things in Sheet View from the Graphics Area (selecting objects) you will send the data to DWG in Model Space - this is a way to e.g. send AutoCAD the Section Drawings for example (I will often create a "Big Sheet" in TBC to create all my sections on one sheet and then select all of the objects graphically to transfer the sections as a DWG in Model Space rather than paper space.
One thing that cannot transfer natively from TBC to AutoCAD is the Drawing Grid - there is no equiivalent object in AutoCAD so you need to explode the sheet grids prior to selection of the sheets or objects to transfer the information graphically.
In the same way that AutoCAD references Model data to their paper space, if you are sending Sheet Data to AutoCAD you really need to also select the Plan View data as well, as that is being referenced into the Dynaviews which will work the same way in AutoCAD - so pick your Plan View Data and then pick your Sheets from Project Explorer and then Export to DWG the combined information.
Alan