1. If commissions were transferred in error, and you just want it back the way it was, you can go into CS-B (View Salesperson Info). Type in the REP # and press enter and the screen will populate.  At the bottom of the screen you will see an EDIT box.  Click on it.  This will allow you into the other boxes showing amounts by month.  You have to enter through each one until you get to the box you need (you can't just click on the box you want) The amount that needs to be pulled back in should  be shown as a negative amount in the commissions due.  Then go to the transfer screen and transfer the negative amount.  ***You must make sure to go back into CS-B and edit commissions due back to what it was before you originally transferred. I would make sure no one is invoicing sales orders. I have done this a couple of times with success, but I'm not sure if it is the IS Tech Support recommended way.
 
2.  I think the best way to change an amount or eliminate a commission is through the sales order.  We often void the invoice (for commission purposes only), then correct the commission and reinvoice. It's the best way to keep all of your records straight and GL balances correct.