I don't know. They were working last time I checked them. A few things changed in the last update for FSX-SE, and I had to redo the entries in the DLL.XML file for FSX-SE.

Not in the C:\Program Files (x86)\Steam\SteamApps\common\FSX\ConfigData\AppData folder, in the C:\Users\[YOUR_USER_NAME_HERE]\AppData\Roaming\Microsoft\FSX-SE folder.

But you can start by copying the dll.xml file from the C:\Program Files (x86)\Steam\SteamApps\common\FSX\ConfigData\AppData folder into the C:\Users\[YOUR_USER_NAME_HERE]\AppData\Roaming\Microsoft\FSX-SE folder, THEN add the lines from my previous reply into the copied one (I hope that's not too confusing).