I used to get annoyed, because to me kaworu is who I was 2003-2005, so it'll always have that negative effect on me. I only changed it back because everyone carried on calling me it, and so there was really no point having a namechange. I personally don't like it, but I honestly don't give a shit anymore (I also really dislike my real name and loved that for my time at sixthform I'd had a nickname, because Monkey is such a better name than Wayne.)
I generally keep to calling people by their current names, unless it's a lot longer than their old one (like treg or mog), but I really don't like using names for some reason, so it's he, or she, or they, or that guy there etc.
Ocean's cool, I'm pretty gay because I was designing monsters for his game if I recall, just before I left GW last september, so I only ended up doing a few before randomly abandoning it.