The .DLL was not meant to help you see those looks, it's only purpose is to help you load looks from scenes if there are scenes for the looks you want.
Speaking of: the first reply you got about your question was something along the line of "some looks only come as scenes, you'll have to load that scene and save the look yourself before you can load them". I might add that some looks only come as "Look presets" or "Appearance preset" without any scenes, and you can only use them by loading those presets.
But without knowing which looks you're talking about, we can't be more specific on why you won't see that look -- so can you give us an example of a look you've downloaded and can't see? Preferable with a link to that look so we can download and test it as well.