I had a symbolic link to my folder originally in appdata roaming and while flight simulator works just fine with it, the universal installer does not. Not sure why the installer has a problem but not flight simulator. I am trying to avoid filling my main drive with streamed and downloaded assets.
Making a symbolic link to the community folder it's a mistake. Yes, it might appear the simulator is fine with it, but only because it's being tricked by the OS that will make it appear the community folder to be there, when in fact it's not.
The reason why the FSDT Installer doesn't work, it's because with that method, you only linked the Community folder outside the standard location, but the UserCfg.opt, which is the one and only place where we can check where the whole content is installed, hasn't changed, as it normally is when you move the CONTENT (not the Community!) using the official method, which in MSFS 2024 can be done at any time, from the Settings icon in the MyLibrary menu.
Please read the full explanation here:
https://www.fsdreamteam.com/forum/index.php/topic,32556.msg205512.html#msg205512The instructions relates to MSFS 2020 folder, but in MSFS 2024 the principle and the method is identical, just with different folder names, since MSFS 2024 settings are found in the %LOCALAPPDATA%\Microsoft.Limitless_8wekyb3d8bbwe folder for the MS Store version, and %APPDATA%\Microsoft Flight Simulator 2024 for the Steam version.
The problem is, MSFS 2024 managed to make it even more confusing than it used to be, because the UI is leading you to believe you are moving just your Community folder, because there's an "Community folder" button below the place where you can browse where to relocate Content. AND, they renamed what used to be called "Content" in 2020, as "Storage":

The key to really understand what's going on, is the small tiny grey horizontal bar that divides the upper part of the MyLibrary settings dialog, from the "Community folder" button. Once you figure it out they are completely separated and unrelated, it will all become clear. You are NOT moving "just" your Community folder, you are relocating the whole STORAGE location, which includes all 3 folders, Community, Official2020 and Official2024.