Want to preview a file from an application you build in Runtime Revolution. Such as a PDF help manual. Instead of launching another application such as preview. If your app deploys to OSX 10.5 or later you can just use quick look. Quick Look supports a number of different formats to preview. The script is in the image file with this post. For more info on what you could do, open the terminal and type qlmange -h  It simple and straight forward to add to your app and might be a better touch than using preview.

(click the photo to see it big)