but it didn't work.
Haven't you said your problem was solved, by having FSX generate a new fsx.cfg ? There's nothing in the fsx.cfg that can affect our product, except the [Trusted] section. In any case, as been explained several times in all threads about missing buildings, when you re-trust all modules, it MIGHT happen that they'll not run the first time. You only need to try again, eventually after a Windows reboot before re-trying.
So, let's start from scratch, is your problem solved or not ?
Do you see the "Addon Manager" menu ?
Do you see the "Couatl powered plugins" menu ?