Why are there a limited number (mixed bag) of A310-300 Liveries in the IniManager?

[Keoki619]

I'm trying to load the fictional livery for Delta for the A310-300 in their current paint scheme.  Its on the IniBuilds.com website but not in the IniManager for MSFS.

In fact the offerings are pretty sparse in comparison; IniBuilds.com currently has a 113 A310-300 Passenger liveries, 92 Realistic, 21 fictional.  The Inimanager used for MSFS only has only around 70 liveries listed and a mixed bag at that.

For example, the fictional livery for American (AA never flew the A310-300) is listed along with Delta in their original livery.  A fictional livery of what the plane would look like in DL's current livery isn't listed in the IniManager but is listed for download on Inibuilds.com.  

[Deleted Account]

The liveries listed on IniBuilds.com are for the XP version of the aircraft, not for the MSFS version.