You are piggybacking on a thread that is fairly old, when KORD V2 just came out.
I don't see any issues using DD Chicago City X together with FSDT KORD, and even together with DD other Chicago airports ( except KORD ), just sure that:
- You keep DD Chicago City on a lower layer than FSDT KORD
- You use the DD *Installer* to DE-SELECT KORD, which results removing it. DO NOT remove it by hand, because their uninstaller does several non-obvious stuff ( removing, renaming, etc. ) that would cause a mess if you remove DD KORD by hand.
Yes, there was a bug in some version of their uninstaller, in which it didn't remove *all* files from their KORD airport, some lights were still there but, maybe, they fixed it in later version, no idea but, in general, when I tested it, there we no issues using all of them together.