Step One: go to versiontracker.com and download Spark. Here’s the link.
Step Two: double-click the download from Step One, and if things go right you’ll see something called Spark on your desktop. It will look like this:
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Open that, revealing this.
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Step Three: open up the Applications folder and open up Spark. You’ll see something like this (without the shortcuts yet):
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Step Four: click the little gear at top left, hold it down, and slide down to “Application.” Now you get another box:
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All you need to do is fill in the box. Click where it says “click to edit” and then press the “trigger” key. Click where it says “Choose...” and choose a program to open. “Calculator” is a nice one-- why not make Calculator be F5? Try it-- there’s really nothing like getting your hands a little dirty.
From that point on, your key will work-- forever, for free. Pretty neat.
If you have trouble, click the link at the bottom of the page and send me an email.