The same tour file can be played in both Google-Earth and the Google Earth Plug-in. If you wanted access to all of the controls as well as the opportunity to have a lot more room for your views and tour, then you would want to open the tour in Google Earth 5.0 itself.
To do so, you need the tour file on your own computer. You can get it if someone sends it to you as an attachment. You can also get it by browsing to its URL. In this case, the file in on my Sites server at
What I have found is that clicking on this file gets you an invitation to download it. I haven't found a way for it to be opened remotely by Google Earth. But no matter. Download it and save -- and remember where!
You can open the file in one of two ways: by clicking on it directly. This will launch Google Earth -- if you have it already installed, of course. Or, by opening Google Earth and then opening that file within Google Earth.
Once opened, the tour will appear in a folder in "Temporary Places" on the left side of Google Earth's window (under "Places"). Find the "tour" symbol in that folder and highlight it. This is the surest way to launch the tour. Double clicking the "tour" will launch the tour. You may also note that a "tour" slider/icon is enabled when the tour is highlighted. You can push "play" just to the right of the slider. (One supposed that it should easier than this. The plug-in starts the tour immediately, but not so in Google Earth.)
Once the tour is started you can control it with the tour controls in the lower left of the screen. Mouse-over that area if they disappear. They will reappear. There will certain limitations on what you can do if you remain in the tour but they are minimal (opening new folders, for example). In general, you can zoom in, zoom out, use the rotation and tilt controls even while in the tour. (The tour is "paused" when this happens.) But if you mouse-over the controls, they reappear and can be used to start/stop the tour and to exit from the tour.