This is what I get from the Ruby Console:
Sketchup.find_support_file('Plugins') H:/Program Files (x86)/Google/Google SketchUp 8/Plugins ENV["APPDATA"] C:\Users\Alison\AppData\Roaming

And no I don't see "LibFredo6 settings..." in the Windows menu of Sketchup. (Edit: After looking at the System Preferences > Extensions I did find the LibFredo6 Settings option and enabled it. So now I do see it in the Windows menu.)

I was able load the Bezier Spline toolbar without any errors but nothing was added to the Windows menu.

Okay I dumped everything out of my plugins folder to start clean again. I loaded the SketchUcationTools.rbz file in SketchUp 8 and opened up the window for it in the program. I selected Autoinstall for the LibFredo6 and restarted SketchUp with no errors. I then opened up the SketchUcation window again and Autoinstalled the RoundCorners v3.0b and restarted this time getting the following errors, I added a picture of my plugin's folder as well:

What am I missing?

@dave r said:

From the first post of this thread it's pretty clear.

I installed the tools from inside my copy of SketchUp 8 using Autoinstall with the SCF Plugin Store tool. I had no previous installations of these plugins and I am getting the following errors when I open up SketchUp now:

It does load the BezierSpline tool without issue. I installed it the same way I did the other tools from the Plugin Store inside SketchUp.

Any thoughts as to what I should try next? At the very least I would like to get the Round Corners tool working.

Thanks