You only need to send $200 once. Send that with your basic registration fee.
You can either send in active application at the same time, or you can send it later whenever you want.
Your basic application will take up to 3 months to process. Active application will take much longer. Even if you send them in at the same time, you will receive your basic membership first, and your active membership at a later date.
I'm not sure about access to these forums. I automatically get access to all the forums because I am a member of the hierarchy (the Priesthood). Someone else may be able to answer that question.