Post#309770
It's not as positive as I remembered, an old post, and things have changed since...
At least we know that the old maps were playable a year ago, when Faerun wasw mentioned in one of the DevDiaries.
From the discussion in that thread, I'd quess most modding commands stay the same, but if e.g. a new unit has been added the modded units' ids must be changed, etc, which might even be possible to automate with a script of some kind.