Can you share (or message me in a private) an iso with ltsc packages included? I would be happy if I could test with ltsc packages. I remember (correct me if i'm wrong) i downloaded from this thread a 19041 with ltsc packages. Works well that 19041 build on a secondary computer.
I don't make it. You can modify 19041 script. (I don't keep it, you have to ask others.) I recommend official release one.