Yes, I have. I am an admin on a couple wikis and a moderator on the Head Soccer Wiki, both of which have the chat moderator rights.
Many times. Mostly because there is a troll or spammer in the chat and all mods are AFK, and I have to report the case to skype or to other mods that are online.
I plan to keep my eye out for any bad conduct in the chat. I make sure to come to the chat every day and warn users that are in violation of the rules. If they continue, I’d kick and eventually ban them.
I think my best contributions are fixing grammar and expanding stubs. Whenever an edit needs to be done, I am there to fix it. I also sometimes add images to infoboxes on pages that need them and work with galleries.
I come in the chat every day and am also really active. I know the rules and whenever I find bad conduct in the chat, I report it. I am pretty friendly in the chat as well.