An update to this, we finally found what the problem was and, guess what, it didn't had anything to do with FSDT and/or Couatl program.

 

The reason was the user FSX.CFG was missing this line, that is supposed to be there in every FSX installation:

 

SimObjectsPaths.5=Simobjects\Misc

 

So, he wasn't just missing buildings at all our airports, he was missing many default objects too. The reason why this line was missing could be either having edited the FSX.CFG by hand, but we also had reports of other products installers that removes it. Our installers don't touch that lines, because they don't need to add a new line, just put files in the Simobjects\Misc folder, which is supposed to be active.

 

It's possible that Couatl disappeared, because it was getting too many error reports from Simconnect, trying to create objects that weren't found, we'll try to see if there's a way to prevent this, and possibly inform the user of his botched configuration.

An update to this, we finally found what the problem was and, guess what, it didn't had anything to do with FSDT and/or Couatl program.

 

The reason was the user FSX.CFG was missing this line, that is supposed to be there in every FSX installation:

 

SimObjectsPaths.5=Simobjects\Misc

 

So, he wasn't just missing buildings at all our airports, he was missing many default objects too. The reason why this line was missing could be either having edited the FSX.CFG by hand, but we also had reports of other products installers that removes it. Our installers don't touch that lines, because they don't need to add a new line, just put files in the Simobjects\Misc folder, which is supposed to be active.

 

It's possible that Couatl disappeared, because it was getting too many error reports from Simconnect, trying to create objects that weren't found, we'll try to see if there's a way to prevent this, and possibly inform the user of his botched configuration.

Thanks for keeping us informed.

Thanks for that, I was just coming here to post the results. Well done to Umberto that was a tough one to diagnose.

Granted, sometimes Umberto's tact isn't always the best, however I chalk that up to the endless barrage of questions he gets bombarded with. One only has to read their forums to understand the number of face palms needed to get through some of them. I will say this; I have every one of their airports, GSX, and all of Flightbeams airports that also rely on couatl and have never had an issue. Ever. All installed, run and work flawlessly. It has never messed up my scenery.cfg, fsx.cfg, exe.xml dll.xml or any other fsx dependent file.