Right now there is a customer number field and then below that there is a customer number section but you can only search by the customer name you can't search by the customer number which is an easier search for those of us that use that information.
This feature was completed and became available in MX Merchant on 7/19.
No really I promise, it's there! Check it out by logging into mxmerchant.com, click on the green Quick Pay button on the left hand menu, at the bottom of the pop up click on Advanced in blue, and within the customer number field start typing away!
We hope this helps speed up the checkout process for you and your team!