This thread belongs in the Questions/Help board so moving it there. Also, doubleposting isn't allowed so I combined your two posts for you. If you forgot to say something, you can use the modify button of your previous post to add it.
I don't think you can create episodes here. This forum is mainly to discuss anything Avatar related. If you have created fanwork, however, you can post it here to share.
As for your profile pic, you just have to go to your profile, click the modify profile link, and then copypaste the url of the pic you want to have displayed into the Avatar URL box. You can upload a picture onto tinypic or imgur and use that url.