Although I worked in the TV industry, I did not personally use most of the techniques that I mentioned. I did hear about them to various degrees and put the pieces together in my mind. At the time I was intensely interested in the techniques but was also immersed in the day-to-day job of keeping TV stations on the air and operating. I will try to show one way that those moving highlights around the border of an object may have been created.
Lets start with a single letter. It is drawn with a black border and has a fill color or pattern. There is also a background color. But the border of the letter is the only thing that is black.
An apparatus is used to expose the film, probably 35mm or even 70 mm. This apparatus has provision for very exact registry using an image plane where a large format (8" x 10" or even larger) positive or negative of the letter can be placed. It will have provision for illumination of various types.
A first exposure of the film is made with just the basic, unaltered image of the letter.
One or more 1::1, high contrast negatives of that letter are made. The areas with colors become completely black and the black area surrounding the letter becomes completely clear. Light can only pass through the border of the letter, no where else. Some hand touch-ups may be needed for any areas that do not become solid black, but that is an easy and routine task in any photo studio.
A negative is placed in the image plane
The film is rewound and a second exposure is made with additional effects added to the light source. One such effect could be filter holders which rotate using small motors. A filter which is all black except for one slit could be placed between the light source and the negative to illuminate only one portion of the clear border area of the negative at a time. The motor would rotate the slit at whatever rate is chosen for the bright spot to move around as wanted.
A second, star filter could be added to that rotating slit or it could be placed on a second rotating filter holder. The two rotations could be in sync (there were synchronous motors available) or it could be at a second rate if that is desired. So the points of the star effect could rotate in sync with the spot that is illuminated or could rotate faster or slower.
A variable density filter could be added to have the light more intense at one area of the letter's outline and less intense or even absent at another. This variable intensity filter could either be still or it too could move or rotate. Color filters which are either still or moving could be added.
If several objects are in the frame and each one needs the same or even different effects, they could be either added to film with additional exposures or they could be on the one negative with separate projector-like light sources, each with it's own set of stationary and moving filters and each striking only one area of the main negative. With projection style light sources, it would be possible to use masks that shape the pattern of the light so it could follow a given feature (the curved top of a letter like R might be an example) only partially around that feature/letter.
The film may be rewound and exposed to many different effects before it is finally developed. Multiple "takes" might be necessary before one of them is acceptable. The process could take days of work for a 10 or 15 second long effect. That's why you only see examples of these techniques in productions that had "deep pockets" financing.
Complete details on this type of special effect are difficult to find. While the type of camera system that I describe was probably commercially available, I am sure there were many custom made modifications and additions. A special effects artist of that era was either a machinist himself or routinely used machine shops to construct the needed devices. None of these additional items would have a make and model number or could be found in any catalog. They were one of a kind results of individual imagination.
This is my take on just ONE WAY in which it was done. I am sure there were others. There were special effects artists/studios in Hollywood and other places who each had there own equipment and techniques. And I am sure I have made omissions or mistakes in the one process that I tried to describe. I welcome any corrections from anyone with better knowledge or experience.
As for your list of specific questions, I am sure that all of the alternatives you list could have and probably were used. As I said, there was a lot of individual creation in this game. And there were trade secrets that were not made known because the artist/studio put a lot of time and money into their development and they wanted to reap the financial rewards. The trade secret thing is probably why it is difficult to find detailed information on this subject. The people doing it did not want it to be known.
One thing I can say with absolute assurance is that the arrival of affordable digital effects systems was a very welcome thing in the movie and TV industries. I watched a number of these come and go over the years and each one was worlds better than the previous one. And often less expensive as well. Today I can do things with my computers and even my cell phone that would have cost hundreds of thousands of dollars or even millions back them.
But the film people used a variety of techniques, often involving many different "prints" or "negatives" of a single scene. The scene could be printed with multiple exposures using those different "prints" or "negatives" along with different light sources and filters. I even personally had "star" filters and soft filters (lady's stockings) for my 35mm and other cameras. But they were just the tip of the special effects iceberg. Rotating wheels with slits could bathe different parts of a negative with changing light patterns. Color filters could be added. Diffraction filters. Prism filters. High contrast negatives of slightly different magnifications could provide an outline. The list is almost endless. Again, the biggest limitations were imagination and dollars. And the movie people had both.
Wow! That is very interesting, would you happen to have more information on the use of negatives with slits and light sources in creating the outline? Like how did the lights move or were they stationary. To add on that, what component was the one that moved? The slit or the lights? What is a simple horizontal movement? Or was it rotation as well? If the lights were the ones that moved, what motions would it do? Would each letter have its own light source or was it one light source for the whole text/object? You mentioned the use of prisms and filters, were there anything in-between the slit and the lights? Sorry if I'm asking to many questions but there is no information which you have just mentioned on the internet. If you do know or have an idea on how they did it exactly or even have a diagram, it would mean the world to me. 
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