Modification of Child Support Order

When and why should I ask for a modification?
How soon will I know if my request has been approved?
Do I need to be present for the Administrative Review?
Do I need to send original documents?
What happens if the non requesting party does not send in their documentation for the Administrative Review?
What if I do not agree with the Administrative Recommendation?
What should I bring to the Administrative Hearing?
What if I do not agree with the Administrative Hearing Decision?
How do I know when the Modification is complete?