InfoPath Dev

I am new to infopath form and i have been learning quite a bit but i am in need of a little help right now.
I have created a bunch of web-compatible forms for the users to submit their requests to be processed. A submitted form will first be screened by an Administrator before fowarding it to a right department so the request can be handle approriately. If a form was not filled in correctly, the Administrator will reject the form and the original submitter will be notify by email (handle through a workflow) and the form need to be corrected by the original submitter. I added a button and set the Action to Update Form but the form was not update at all when the changes are made the Update button was click.
So here are my questions
1. How do i implement update feature for my form? and how does the update button work? Up to now all development was done using infopath 2007 and sharepoint designer therefore i would like to stay in the same environment.
2. How do i disabled the submit button if the user edit the form otherwise a new form will be saved when the user click the submit button again.
Thank you in advance.

You were just confused by the semantics of Update. True, users are "updating" the form, but the action to perform is just a re-submit.  You submit the form every time you want to change it, so that's all you need to put on your button.

Use my technique here:

InfoPath – Auto-Generating Filenames

You just need to make sure you use a technique like that to ensure the same filename is used every time you re-submit.

I followed the technique instructed in your link and the edit feature worked wondefully but here is the side effect:
I have a workflow attached to the form which suppose to "automatically start this workflow wheneve an item is changed" and when the user edit and resubmit the form the workflow started. How do i get around the issue?
Thanks

If you don't want the workflow to run every time it is edited, then why is the workflow set to run on edit?  You have to decide how the workflow is supposed to work.  Should that setting be changed?  When do you actually want it to run?

Anyway, if you need it to run on some edits but not all, then put a step at the beginning of your workflow that has a condition or set of conditions.  Check a field (maybe a new field with flags set) and based on that field's flag, tell the workflow to step or let it continue.  You just have to add logic.  The workflow will still always run, but you can stop it before it does anything.

i have a autoincrementing number which i use for course request. once the course is completed we have to disable the course. however, when disable button is clicked it is creating new column and disabling the latest row rather than currently existing one. how do i make it disable with autonumbering conflict.