During beta testing of v2.35, I discovered that a HUGE (80GB) torrent I am seeding was created with a mostly empty folder, containing several files of 0 byte length. That caused errors on move attempt but v2.35-a6 fixed that issue. Thank you KH and team!

I searched, and found another torrent with the correct contents of that one mostly empty folder that was added to the huge collection.

I don't have a good grasp on the implications of the new folder merge functions etc but am wondering what tricks I can do with them.

So I have an 80 GB torrent (Torrent A) that is a topical collection of folders and files, with 1 folder being incomplete.
I have a second torrent (Torrent B) that has the complete content of that folder.
I also want to build on that collection and add to it.

First question: Can I merge the contents of Torrent B with the contents of Torrent A, create a new corrected Torrent C metadata file, renaming but leaving the 0 size files in place while adding the complete source files that were initially intended?

If my assumptions are correct, I should then be able to continue seeding Torrent A, and Torrent B and the Torrent C I would create of the corrected collection, all from one location on my HDD without having duplicate copies of the files. Am I good so far?

The next thing I would like to do is update that corrected Torrent C, by adding extra files and folder containing more media on the topic, without having to have redundant source files (iow a single file could be used for seeding in multiple torrents). The result would then be Torrent D.

What I am looking to do is create a workflow that allows for making a torrent collection, then keep updating it over time and sourcing both the original torrent and any updated torrents from the same seed stock and the ability for peers to get any revised torrent, and have tixati "merge" it with the original version then only download any new files needed to keep their collection up to date.

Is that all possible to do with the new versions of Tixati?

You cannot simply edit the INFO dictionary of the torrent to merge two torrents.
Firstly you would need to have the binary data for A and B.
You can theoretically seed A and B, and create C from A+B . . . but the folder would need to be all\the\same\path... Creating a torrent from disparate data is not supported. In any client afaik.