Topic: Can't install and Run SimpleViewer Script in Photoshop

I just downloaded SimpleViewer v1.8.5 and followed the online instructions for how to install and use it with Photoshop CS 2. However, when I try to run the script in Photoshop, I receive an error that says "Error 2:  Document Undefined. Line: 8". Any help is greatly appreciated! And it looks like I'm not allowed to post any links yet, so if you need screen captures, I could send them to you personally.