What do you mean with "it's also taking up more and more storage" ? Unless you are continuing to reinstall into different locations, this cannot happen.
What do you mean with "I deleted the Addon Manager file, and the Universal Installer...to reinstall" . You must use the Universal Installer to reinstall, so you should not deleted it for sure.
Or, maybe you wanted to say "I *uninstalled* the Universal Installer" ? That would be the only way you could choose a NEW different location in fact and, if you do that, you WILL end up "taking up more and more storage", since you would create multiple copies and leftovers, which explains why your folder there is almost empty: maybe you installed another copy in another place.
To fix this, try to remember in which other location you might have installed extra copies, and remove ALL of them. The uninstall the FSDT Universal Installer from the Windows Control Panel, and if you still have any other Addon Manager folder anywhere in your system, remove it.
So now, you should be able to start again from scratch, and reinstall the FSDT Universal Installer again, and then GSX Pro.
Be sure you add the complete Addon Manager FOLDER ot the Antivirus EXCLUSIONS, if you don't do that, and your antivirus is defective, it might remove the couatl64_MSFS.exe file.
