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The problem the customer had was not caused by JoomSEF, but by incomplete configuration. The solution is described in our FAQ.
We admit, that the response to support ticket was not timely as we would ourselves like it to be; however we guarantee no support feedback times (unless agreed by paid support agreement).
Even when this was not our product fault, we have agreed on a partial refund with the customer (ignoring the purchase conditions approved by the customer that refunds for already downloaded software cannot be made).