Hello and welcome to the Skype community, thanks for this interesting question.
The most important trait of a moderator is being well-balanced and even-tempered. Because, unfortanately, on every forum community there will be visitors attacking you and your moderation directly because you will be the face of the community and / or company. In addition to that she or he needs to be able to take a neutral point of view and only follow the guidelines set up for a community regardless of the content of the discussion in a thread. The third skill is especially important on support communities: You need to have the empathy to be able to take a step back into the position of a new user. When you are using an application for years and are familiar with every nut and bolt you need to be able to moderate a "newbie" question with the same attention as a question coming from an advanced user.
I hope that answers your question. Maybe one of our moderators can share some of his or her own experience as well.