hi Alex,
it's possible the problem is not the key.
Open Firebug in Firefox, and go to the browse.
Now open the firebug "console" window, and then click on the "Next" button.
You should see the response apepar in the console. Open the response, and choose the XML tab. If you see any kind of error there, then that implies something in the response was not xHtml compliant. This is the most common reason for the browse buttons to fail.
see attached pic.
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