The download is in the form of a zipped foldeer (.zip file). Once you have unpacked it, it will contain the Java executable(s) (.jar files). These jar files are identical to the files that are bundled in the Mac OS X application bundles, or installed on a Windows system by the installer. They may be used on any platform which has a Java run-time (1.6 or later) installed. Indeed, on Mac OS X and Windows, it should be sufficient to double click the jar file like any other application. On Linux platforms, it is possible that they need to be run from the command-line, eg, " java -cp ClickRepair.jar ClickRepair" once you have changed directory to the one containing the jar file.
You are unlikely to get messages from Linux asking about trust. Nevertheless I advise that you read the security information on my site.
I do not have a license retrieval system. The first couple of uses after you enter the license code, the About Box will appear and prompt you for 10 seconds to print (and keep safe) the information. The About Box may be used in this way at any time, except after your computer has crashed, or been disposed of!