Hello,
The ability to use the "PayNow" option in the MyAccount module is currently only available with the Credit Card Payment Method although I do think that adding the option of other Payment Method would be useful so I wil;l add this thread to our Enhancement Requests forum.
If you have budget in your project and would like to be provided with a fixed quote to sponsor a portion of the programming to add additional Payment Methods for the Pay Now option, please send an email with a link to this post to sales@smith-consulting.com. We quote all feature enhancements below cost since it is enhancing the module and in most cases we can start work within a week.
Thanks,