THE WORK is Add an other button which open an other page (_blank) for Bank Transfer.
This page is a formulaire which feed a table in data and send a mail to my mail (for example in test mode). Of course in flash with this button, you must send to TOTAL_PRICE to the php page. In the mail, send all data of user (this table is phpSP_users in DB ;-)). You can send also an order ID.
All explanation in attachment
Could you increase the width of this swf... To 95 % of screen ;-)