Do credit card refunds count as a "payment"?

Probably depends on the CC supplier, however with Egg any credits do indeed count as a payment,

(about 500).

I had an odd experience with Cahoot. I stopped using their card in the Spring of 2003 (when they ceased cashback) apart from a small continuous DD. A week after I stopped using the card I received a refund putting me into credit that was whittled away by the DD over a period of six months.

The card was set to pay in full each month and in the month the balance was due to go negative it was showing that I only needed to pay three pounds. I expected that to be collected but it wasn't. Apparently the system saw the fact that most (but not all, as in previous months) of the amount due was paid (by the now whittled to nothing refund) as a part payment exceeding the minimum balance being made, thereby over-riding the 'pay in full' instruction.

After getting past the typically useless front line support staff the matter was quickly and amicably resolved by Cahoot. Clearly these things depend on the programs each issuer users.