Proper Bodyslide conversion

[GoodCave]

My problem description may sound kinda retarded, but I just wanted to convert one outfit, specifically - an df_t33 boots from UNP to CBBE Curvy.
I've read and watched a few guides, but they're outdated and irrelevant (or I just figured something wrong).
So there's what I did (based on what I saw) :

I've created project in Outfit Studio, loaded a body reference from meshes/actors/character/character_assets/femalebody_0 (since i've discovered that my character's body has low weight), loaded an outfit mesh (which is meshes/df_t33/boots_0) and with the "decrease the mesh volume" brush edited it.

So the hesitations of propriety started at this point, but i've decided to export the edited mesh and overwrite the existing one, but it didn't help, nor as project saving and further bodyslide project building.
Will be appreciated for any help.

[Mookeylama]

i'd love a df_t33 bodyslide files. uunp tho. and hopefully more optimized nifs. they're like 13mb each