http://gumroad.com is a third-party website for selling and buying digital products. We use it to sell OMFramework and OMAdmin. If you have purchased OMF from it (instead of http://opencart.com), an account will be created for you. You can use this account just as you would use your OpenCart account—to download the latest OMF updates.
We do not have access to the credit card data you enter on Gumroad.