I also found this bit of very useful information (by accident), so I'm passing it on to those of you have FSX SE / Steam
Heres what the article says ya can do to FSX SE, to help with adding , Add Ons (Payware or whatever) !!
*** SEE THIS LINK AS WELL / READ IT : http://swfsg.blogspot.com/p/fabios-blog.html
" This utility does much the same as the Flight1 Registry Fix, but instead of putting in the MS FSX.EXE path, it puts in the "FSX-SE FSX.EXE path", and thus "installers" that were expressly written for FSX "can now find the FSX-SE FSX.EXE", and thus these installers can run normally.
Here's the text from Rikooo:
Here is a small program created by Rikoooo that make "FSX Steam Edition",, detectable by the oldest auto-installers of Rikoooo.
Rikoooo's Auto-installers will believe that "FSX Steam Edition is in fact FSX".
It will simply copy the contents of the registry key named, "HKCUSoftwareMicrosoftMicrosoft GamesFlight Simulator - Steam Edition10.0" AppPath in "HKCUSoftwareMicrosoftMicrosoft GamesFlight Simulator10.0".
Giving the "installer" the path to "FSX Steam Edition" and fixing the issue.
