Once you save a character to the library 2 things happen, depending on your Poser preference settings. If you have 'use external binary morph targets' checked in the misc tab of preferences the character will be saved to the library with an additional .pmd file. A .pmd file stores all of the morph data (deltas) in a compressed format. The .pmd file will be named exactly as the name you saved the character as, just a different extension. If you save to the library without external binary checked the morph deltas will be embedded within the .cr2 file. Files with embedded deltas tend to be larger and take longer to load. Considering the amount of morph packages that are often loaded onto a Daz character, embedded morph .cr2 files can get ridiculously large and take long to load. Downside to .pmd is that it's a seperate file, so it's vulnerable to being lost or misplaced if you carelessly shuffle things around... the .cr2 calls on the pmd and expects it to be in a certain referenced place, if it can't find it your loaded morphs won't show up.

If this is a fresh install of a gen 4 daz character (m4, v4) and you've loaded morph packs onto it and saved it to the library, the morphs are either embedded or external. If you simply have a m4/v4 saved in a scene the morph data will be either embedded within the .pz3 with the cr2 or externally as a .pmd, with the scene name.pmd extension accompanying the pz3.