If this ticket started in Asia then you could only have two stopovers; no extras allowed. So it must have started outside Asia.
Pat - what you purchased was not an extra stopover, it was an extra segment. There is no restriction on stopovers on a OneWorldExplorer except in the continent where you started (where the limit is two and you cannot buy more). The normal limit on segments in Asia is four. You can purchase up to two more. But it does not matter where you transit or stopover. I do not see any reason why you should be charged anything extra EXCEPT the additional tax associated with a stopover in HK instead of a transit. There is no additional charge on the ticket itself.
[This message has been edited by christep (edited 04-21-2003).]