Sorry, I have recently began describing one of the easiest ways to navigate the warped space that is C3D is to use the Toolspace Transporter. This technique will allow the user a much more direct experience with the data in the file as well. I will describe how you use the Transporter below.
Somewhere on your Monitor the Blackness of the Drawing window that is your model space, there is also the Light which is the Prospector Tab of the Toolspace. Embrace the light. Using either Master view, or Active Drawing Only, one may open the Tree view of the Drawing. The treeview is the portal to the data in your model.
As one digs down into the root level of any object collection (point groups, corridors, assemblies) the fastest way to get to that object in the Blackness of the drawing window is NOT to Pan or Zoom.
One right clicks on the object in the tree then selects the Zoom To option and C3D responds by centering that object, or group of objects right in the screen. By running up and down the tree and Teleporting to your data, you will gain a lot of speed. I think it would be call right speed?