[Location of manual different than what listed under FAQ]

Mine was also in a different folder than what it says in the FAQ.

(Steam Edition)

%Appdata%\Microsoft Flight Simulator\Packages\Official\Steam\microsoft-aircraft-a310-300\Resources\Documentation

[Liveries for MSFS A310]

I was struggling with this as well.

I had to go to the gear icon to access the settings in the iniManager, and click on "Scan Now" in the middle next to the Community Packages Folder for MSFS.

I can now see all the liveries (even for my other addons like the Fenix)