I only have one livery for the 757 PW Base Pack which I rarely use, and I have none for the RR, or Freighter. I just select a model, and fly it.

This also applies to quite a few addon aircraft from other developers. I just select a model (with the developer livery), and fly it. Some also come with other liveries, but in the end, I'm still only selecting one in the developer livery anyway.

I'm only interested in flying them, and seeing as I'm not flying in Vatsim, or the like, nor in a multiplayer mode, it doesn't matter to me.  :-/