Have you restarted SketchUp after the extension / lib were installed ?
That should sync everything.
The toolbar & menu items should show up then.
Fredo's extensions are listed under a submenu in the Tools menu... did you look there after a restart ?
Simply paying for a license doesn't license the extension. You need to activate it in the appropriate submenu under Tools...
If you have tried all of this without success, then please comeback for further help...