I think they're just non-exclusive, so any relationship is likely to have a mix of some degrees of more than one kind of attraction, and one can lead to another or change over time.

Communication is definitely the key. It's hard to convey all the nuance in a single world, or even a set of words. Like, once I saw someone refer to themselves as "bi-sapioromantic"... which kind of answered some questions, but raised others. Another time, a couple people seemed to hit it off... until one of them said "before we go any further, can I see your ankles?... no, that wouldn't work, sorry". I don't know what their deal was, or whether there even is a word for it, but at least they communicated effectively.