In update, you can click many times in button Apply Changes.
I suspect what needs to be done here is to disable the Apply Changes button once it has been clicked. (client.update.gui.UpdateSummaryDialog, line 146)
But I'm not sure how to test this, especially since from SVN, I am running the most recent version, and this Update Summary dialog only comes up if you are running a previous version. I could get a previous version from SVN, but then the release.xml that is required: what do I do about that?
I'm officially requesting some insight on how to test this. :)
perhaps you could give Johnathan the details.