Anyone is free to make such a video tutorial. In fact its probably better that it not be done by the developer since its is then more likely to reflect a user's perspective. The nature of the question that started this thread did not require a response from the developer (who has not created such a video.)
TS Pro is a niche utility, i.e., it focuses on a specific aspect of flightsimming - one that, if the questions posed in the ADE forum are representative, is not generally understood. Use of TS Pro requires a comprehensive understanding of terrain techniques and the way terrain integrates into Flightsim. Without that, use of TS Pro is unlikely to be satisfying and, not surprisingly, the user manual is not likely to be helpful since it assumes that understanding.
Tools such as TS Pro consume many hundreds of hours of development time. Production of a comprehensive user manual (which is not meant to be entertaining) is not an insignificant understanding. Ungrateful users who are not prepared to spend a few hours reading and understanding the user manual can always look for another utility to serve their purposes. There's little you can do with TS Pro that can't also be done with other tools , say, sBuilder; but, you'll have a lot of/more grey hair by the time you finish.
Don