• The text field on top of the dialog lets you specify a file to output the recording to.
  Default is "..\Previews\path_recording.cnp", You can type in a path manually, too.

• Press the Get... button to select the file and path.

• There are two recording options: EventDriven and Polled. They can be selected from the drop-down list next to the START RECORDING button.

• EventDriven Recording will only record changes to the camera and ignore pauses. This means that if you move the camera, then pause for 5 minutes to drink tea and go back and rotate the camera, the pause will not be recorded. This also means that a large number of samples will be recorded, as many as the issued viewport redraw callbacks.

• Polled Recording will record everything that happens, including pauses. It will record at a fixed frame rate identical to the scene frame rate set in the Time Configuration dialog, by default 30 samples per second.

• Information about your choices and feedback from the tool can be monitored in the listbox in the middle of the dialog.
   

• To start recording, select a viewport and press START RECORDING. The button will change to STOP RECORDING.

• To stop recording, uncheck the STOP RECORDING button.
  If you switch to a different viewport while recording is on, it will be disabled automatically. If you close the dialog for some reason, the recording will also be disabled and the file will be closed before exit.
   

• Currently there are two animation import options: Realtime Animation and
  All Samples.
  When recording using the EventDriven Recording option, a large number of samples will be saved. Every sample will have a time stamp in milliseconds.

• If you want to create an animation that runs in realtime (using the current FPS settings of the scene), select Realtime Animation. Keyframes will be created only on full frames, all other samples will be discarded.

• If you want to create an animation that has all samples recorded in the file, select the All Samples option. A keyframe will be created from every sample, completely ignoring the time stamps info. Depending on the actual redraw rate during recording, the animation can run longer or shorter...

• To import a file, press the IMPORT ANIMATION... button. A file dialog will
  let you pick a .cnp file (currently stored by default in the \Previews directory).

• If nothing is selected when importing, or more than one object is selected, a new free
  camera will be created and animated using the information from the selected file. The camera will be automatically selected AND placed in the currently active viewport.

• If a single camera or ANY OTHER scene node is selected, the animation will be applied to that object. (but you will be prompted first so you can still create a new camera instead). This lets you record a viewport but apply the keyframes to something else, like a Dummy, a Teapot, a Light etc.
  The imported animation will always start on frame 0. The animation segment end time will be set to the last frame imported if the current segment is too short.

• Note that you can create a spline path out of the keyframes using the
  Motion tab>Trajectory>Convert To menu. Since a spline does not record
  rotations correctly, I decided to stay away from spline creation and record
  the complete transformation matrix.

• Some basic settings of the Walkthrough mode incl. Level, Step Size and Sensitivity are exposed as controls in the dialog. You can also enable Walkthrough mode using the Enable Walkthrough button.

• You can record ANY viewport including Perspective views and Orthographic views.
  NOTE that Importing an Ortho viewport (or example Front or Top) animation as Camera animation will contain only the Pan but not the zoom info.

• Download the MS file, save under \Scripts
• Unzip to \Scripts
• In 3ds max 7, go to MAXScript>Run Script... and select the file
• Go to Customize>Customize User Interface>Toolbars, locate "Record Viewport Navigation" under "Bobo_s Tools" category and drag to a Toolbar.
• Press the new button to open the dialog.