According to a recent post by PMDG, they recognise that there products don’t work with the Steam edition and they are working on it.
They say that once they have fixed the compatability errors that you will be able to install There products into both. We do have a date, 16th January is the worst case scenario and best case is the 9th January.
We are still sorting out the details here, because we have a number of potential customer groups we need to address.
Specifically we need to determine how to address the issue of customers who want to redownload the product in order to get an FSX:SE enabled installer, and how that will be addressed in line with our existing redownload policy. We also need to determine if/how we can fairly support CD/DVD customers who wish to convert to FSX:SE, as updating their CD/DVD is obviously not feasible.
I anticipate that there will be a range of questions along these lines, and we are working to address them internally. We will communicate the details once we have made some decisions.
Additional Products for FSX: SE:
I have specifically addressed only the NGX and 777 in this update because these are our priority conversions at the moment. The JS4100 will follow, and then we will evaluate the 400X and the MD-11. More details will be provided on those as we get the first couple of conversions off of our plate. I would estimate ETA on those three product lines by the end of January as a worst case.
It appears like they are fully supporting FSX SE so maybe soon you will be able to get rid of the boxed edition. To see the full post click here