Here goes.

First you need winzip or some other extractor. click on the selected aircraft. Choose to save it to your desktop. Next go to your desktop and create a new folder, call it whatever you want to. Then click on the downloaded file that will contain your new aircraft. It will automaticly open winzip, click "I agree" then click "next" several times, now a window will pop up with the files you have extracted, all thats left to do is select all the files in the window (ctrl a), then just drag them by clicking and holding your left mouse button on any icon in the window. Drop the files in the new folder you created on your desktop. To use the new aircraft just open FMS, you will have to select model, but it will not be there, you have select desktop from the task bar at the top, then select the new folder, now just click the aircraft you wish to fly and it will load just like any other.

Kind of diffacult to explane, if you get stuck u can email me [email protected], and I will be glad to try and give u a diffrent method of extraction.

good luck.