Hello,
Is it that you cannot unlock Espionage after upgrade, or is it that you cannot unlock the folder protected by Espionage?
As for uninstalling, with Espionage 3 there are no background processes only the application itself, so to uninstall it, simply trash the application. However if you want to delete the data too then you need to delete the /Users/[your username]/Library/Application Support/com.taoeffect.Espionage3 folder.
Note that your home Library folder is hidden since Lion, to enter into it from Finder, switch to Finder, click onto “Go” menu, hold down the option key and select Library from the menu list.
To reset Espionage and start from scratch, you just rename (or delete) the aforementioned folder and launch Espionage, it will recognise the missing folder and run you through setup again.
However, I'm interested what went wrong because you are the second who reports this problem (although, if that would be a general problem, I would expect much more reports), and so far I did not get any further details on this. So would you be so kind to answer the first question.
Thanks
Zsolt