@Spree Developer: I am in the same situation as yours. I want to integrate PayUMoney payment gateway to my spree site (
www.tailoringhouse.com) but I don't know how to proceed. I have made a payumoney.rb (after referring other payment gateway files like Worldpay.rb etc) file in spree_gateway gem inside models/spree/gateway/.
Can you tell me how did you integrate your custom payment gateway? I have payment gateway API ready with me.