The error message you are getting is related to the Gatekeeper system in OS X 10.7 and later. The reason you are seeing it is that the software is being downloaded from the internet and it is not digitally signed by an Apple Authorized developer. I am offering these scripts as free downloads and software development is not something I’m doing for profit. These are just things that I’ve developed for my own use and wanted to share with the world.

There are three choices to how you can still use the tool outlined above.

1) You can temporarily allow “All apps downloaded from Anywhere” in the General Tab within the “Security & Privacy” system preference panel. Launch the “Lock Screen.app” and select Open in the Gatekeeper dialog box. See THIS ARTICLE for more information about Gatekeeper, what it is and why it is doing what it is doing.

2) You can use Stuffit Expander to unzip the file linked above. Stuffit Expander bypasses the Gatekeeper system.

3) You can copy the AppleScript in the black box above into the “AppleScript Editor” and “Save As” your own “application”.

Any of those will solve the problem for you.

If I get several more of this type of request I will look into going through the process to get on Apple’s Identified Developer list.

sometimes it’s much better to just read the documentation instead of reinventing the wheel using weird solutions.