I have "Couatl powered products" in FSX but I dont have it in P3D (I have only "Addon Manager" in P3D Addons menu).
Then you might haven't configured the antivirus to exclude the Couatl.exe file from scanning in the P3D folder.
- Reinstall into P3D with the antivirus turned OFF
- BEFORE launching the sim, configure the antivirus to exclude the following files from scanning:
YOURP3DFOLDER\bglmanx.dll
YOURP3DFOLDER\fsdreamteam\couatl\Couatl.exe