Simply reading the warnings would've gotten you to the solution, not to mention the numerous mentions in previous pages about how "let the program decide" does not work with multiple files having the same name, which as of a recent change in file structure includes custom body files.
"I'm no expert at modding" that does not stop you from being able to read warnings, one of which, as previously mentioned, prompts you about whether or not you want to continue, telling you it will not work properly with multiple files containing the same name, something that only happens once it detects multiple files with the same name...
I really do not know how to make this any clearer...
The problem was that if I were to do it the way you just stated, I would not have been able to have the advanced slider options. When I saw someone come up with another solution (ie placing all files from .resorepless into the patch file), I tried it, and it worked without issue. It's not as though it requires as much effort though, as all files patch, and I have no issues of same-named files walking on each other. Granted, most of the mods I am using are fairly simple, I have yet to come across any errors doing it this way.