I have no idea what you mean by "creating a new Master copy of the package file" but there is no direct way to import from Photo into Lightroom. You have to get your photos onto a local hard drive from Photo (can't tell you how to do that) and import them into LR.
Thanks. The Master is iPhoto or Photo's data file. It's called a package file and is the unadulterated version of all your pictures. This file isn't openable by Lighthouse directly but by making a copy of it and pulling it onto the desktop Lighthouse can import it (according to Adobe) but I am not having any luck creating this copy. Thanks for your suggestion.
You cannot copy the folder called Masters in the package called Photos Library, is that correct?
Did you convert an iPhoto or Aperture Library to create the Photos Library? I ask, because apparently Apple uses hard links for some of the files back to the other libraries, which might have an effect. Are you using the Finder to copy the Masters folder somewhere? what messages do you get when you try to copy it? It is required that a new copy be somewhere else before you can import it in Lr, it can't stay in the Library