any TCW files in the "Samples" folder do not have the relevant scenario files included.
Should you run an animation and save the scenario file, this scenario file can be viewed and edited in a text editor.
You can load and run any number of different scenario files, and, providing the actor names remain the same, all will/should be well!
Presets are coded scripts, which if you are keen, can be altered to suit any particular need, or, just used as a coding reference for your own examples.
Any custom scripts, that you place in the script editor, are run first for each frame of animation, and will always be visible in the the script editor if saved in the scenario file.
You might also like to look at the command ExtractFrameFromAvi, which might be useful for your purposes.
Lastly, if your animation is long, time-wise, you could run an animation in wire frame and stop at the required point. Then render the drawing for one frame, remembering to undo the animation afterwards.
I hope this helps, and, makes sense.