Hey! Are we able to apply a credit to a customers account, so they can spend it on their next order? Not just a gift voucher but an actual dollar value in their account???
I've only been able to do this via the Gift Certificates.
When a customer places a return request, I give them three options: Refund, Exchange or Store Credit. The Store Credit is issued via the Gift Certificate process right thru the Return process. It works and the customers are satisfied with it.
If on the other hand you want to offer some credit Promotion, you should look at the options available in the Promotions. Promotions will issue coupon codes, reward points and discounts in the cart. It's very similar to a customer credit but based upon criteria you choose based upon what activity is taking place in the cart.
The easiest way is to enable the Reward Points Addon, add the users to a Group and make it a point per dollar amount.
I started writing a store credit addon but the lack of interest in it made it commercially nonviable to pursue at the present time.
Ok thanks guys! I was hoping to be able to just say "hey you are such a great customer heres $20 in your account to spend’ But gift certs will hve to do for now 
I am also looking to do this but I want to say that they can only use the gift certificate if they spend over x amount when placing order. Is this possible?