I'm getting the same error "Please have a single group or Component to bend selected before activating the script."

I'm getting this after doing the following:

1. Creating a tube (circle and then elongating it)
2. Making the tube a group
3. Drawing a straight line along the bottom of the tube
4. Making my arc line in the same (red) plane.
5. Selecting the group
6. Starting the script
7. Selecting my straight line ("start" and "end" appear)
8. Selecting my arc line ("start" and "end" appear)

At that point - according to what I saw in the video - I was expecting the model to make the tube follow the path of the arc line. This doesn't happen. When I click "Enter" nothing happens.

REFERENCE:
Google Sketchup Version: Google Sketchup 8
Computer OS: Microsoft Windows XP Pro (2002) Service Pack 3

Am I doing something wrong or is there another issue here?

Please advise. Your help is greatly appreciated!