The ReadMe that came with it is pretty clear I think:
In order to run Carenado’s aircraft on FSX, FIRST YOU HAVE TO INSTALL CARENADO’S AIRCRAFT IN THE PATH WHERE YOU HAVE FSX. (EXAMPLE: C:/……./FSX)
Then follow these steps:
1. Unzip the file “CarenadoFS9toFSX.zip”. (Just double click on it and move the file “CarenadoFS9toFSX.exe” to the desktop).
2. Double click on the file mentioned and click on “NEXT”.
3. Choose the path to your FSX folder and click on “NEXT”
4. Click on the “START” button.
5. Leave the check mark on the “Launch Carenado FS9 to FSX” option and then click on “EXIT”.
6. Follow the instructions on the screen and you will be all set after a couple of seconds.
The first time you use select the aircraft you may be prompted to “Execute” or “No Execute” by the Microsoft Security Alert System, just ignore it and click “Execute” to install the gauges. Then click on “Yes” in the next dialog window. Repeat this sequence around 7 times (this will depend on how many gauges has the aircraft)
You can keep this software installed in your PC, so every time you need to install a Carenado’s product on FSX you can use it after installing the aircraft on FSX. (You will have a direct access to the software from your desktop)
THIS PROGRAM ONLY ALLOWS RUNNING PREVIOUS FS2004 AIRCARFT DEVELOPED BY CARENADO ON FSX AS IT WAS ON FS2004. IT DOES NOT ADD ANY NEW FEATURES OF FSX.
Carenado
Unless the program works completely different than that.
Crash

PS Reading this ReadMe again. It's not very clear is it? You have to install the aircraft in the path where you have FSX? Not in the Aircraft folder? Now I don't have FSX so I can't actually tell how the FSX structure looks like but some things might go wrong here.
Crash ???