I actually think the "arrow" means that you have a post in that thread. A red envelop with an arrow means you have more than one replies. An open envelop means that you haven't replied to it, and it doesn't have many. Red envelops mean more replies.... Something like that.
As for the ticker, you need to be a member for 20 days? Or 2 months? Something like that and have 20 posts. Then you can edit it in your user CP - edit signature.
I've decided to leave 3FC, In the crowd of so many, those of us with no success that have the audacity to feel bad about our incredibly slow and almost stagnate weight loss, are merely a nuisance to those that are successful. I hope everyone else finds the support they need.