File types:
VaM File Types .json The basic scene file for VaM is the .json file. Also used for Subscenes \Saves\scene \Custom\SubScene .vac Legacy compiled scene files. These are not commonly used anymore. Originally the scene file when packaged into a "vac" for sharing would compress the assets into...
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DSF is not needed, that's a DAZ file, vmb/i are morphs. The PNG are textures for the clothing according to the names.
You can put files anywhere you want as long as the paths are correct. Naturally, best to mimic as close as possible VaM's folder structure to have a clean and consistent resource. Do take a look at the guides regarding VARs.