Rob Randazzo of PMDG tonight posted this update regarding PMDG's position regarding compatability of their products with FSX-SE. We quote:
In late 2014, Dovetail Games acquired the rights to continue development of the former Microsoft Flight Simulator franchise and announced that they intended to put FSX into distribution on the Steam platform.
This product was released without much fanfare- and unfortunately has left us at PMDG a bit in the lurch because we haven't seen the product in operation and thus aren't prepared to comment on whether our products are compatible or not.
I suspect that all of our FSX based products are easily compatible with FSX SE, but obviously we need to go through the process of confirming this, **AND** we need to examin the installation processes to determine how to update the installers so that you can use them with FSX SE if desired.
Normally this would be a quick-hit kind of thing, but most of the team is on vacation for Christmas/New Year- and we had no advance information on the platform layout, etc- so it will take us a bit of time to get caught up.
We will keep you posted- but please bear with us while we work through the process...
ADDITIONAL NOTE: In various other threads I have made some comments regarding PMDG's concerns as a developer in the community- and our concerns about Dovetail's stewardship of the former MSFS platform. Some folks seemed to misinterpret these concerns and got it into their heads that PMDG isn't supporting FSX SE... Those conclusions were incorrect... so if you see anyone commenting along those lines- please point them to this thread for correction.
PMDG is supporting our products in FSX SE... We just have to make some tweaks, as previously discussed."
Your can read more in the PMDG forums here on AVSIM.