The installation can't be easier, just run the installer, everything needed is of course installed automatically by the installer so, you really can't do wrong.
If you don't see the Addon Manager menu (and I presume you don't have the Couatl menu too), something is not right. And, fact you haven't even been asked permission to run both modules, is also not normal. Not having the two above menus, is not a problem just for the installation or activation: without them, none of our products will ever run.
The most common cause for this, is the antivirus so, install as follows:
- DOWNLOAD AND INSTALL with the antivirus entirely OFF
- Uninstall GSX. Reply YES when asked if you want to remove the Addon Manager and the Couatl Engine. Reply YES to both questions.
- TURN OFF your antivirus. Don't just exit from its interface, but turn off the real time protection. Actual wording changes between products, however, it's the option to scan every file that gets open in real time, without user intervention.
- Reinstall GSX (using the full installer in this case) with the Antivirus TURNED OFF. Don't launch FSX yet.
- Configure the antivirus to exclude the following files from scanning:
YourFSXFolder\bglmanx.dll
YourFSXFolder\fsdreamteam\Couatl\couatl.exe
YourFSXFolder it's usually C:\Program Files\Microsoft Games\Microsoft Flight Simulator X, if you installed it in the default folder.
- Now you can turn the antivirus back on, and launch FSX.
- Check you are seeing BOTH the "Addon Manager" menu AND the "Couatl powered products" menu under the "Addons" menu.