We're just setting this up as a PoC, and as part of the testing, we've noticed that if you have a zero-cost, there's no option to cancel the order.
Setting the cost to 0.01 re-enabled the cancellation request option.
Also, you must have a payment gateway even if you're offering free servers. Strange use case, i know... setting to "Bank Transfer" with dummy info worked but a little clunky.