That's correct. New girls will pick up the new characteristics, but pre-existing girls will not change. A copy of the girl is put into the save file with the generated stats. That copy is modified by game play, and will not be affected by changes to the original .girlsx or .rgirlsx file.
This conversation reminds me that I have not explicitly stated anything about my expectations when I update a pack. I make no promises whatsoever about backward compatibility. File names and numbering will change willy nilly. When grabbing an updated pack, the safest thing to do is delete the girl's directory, and any .rgirlsx and .girlsx files, and then unpack the new content into the appropriate places.
Speaking of which:
- New dungeon fairies and corrected stats for Abigaile Johnson, Bibi Jones, Bibi Noel, Charmane Star, Christie Stevens, Clanddi Jinkcego, Devon milf, Gianna Michaels, Jenaveve Jolie, Kira Kener, Linda Park, Madison Ivy, Samantha Saint, Sharon Lee, Stevie
- Found some pictures of Bibi Jones in the Bibi Noel pack, which I moved back to the Bibi Jones pack. Update both packs to fix the problem.
- Added Katie Morgan (she's working again!), Krystal Boyd, Lacie Heart
- Removed the .ani files from Samantha Saint and Sharon Lee. I'm not sure they ever worked, to be honest. Even if they did, I much prefer having one file contain all graphical information, rather than have to worry about keeping two filenames in synch. I've replaced the .ani files with appropriate .gifs.
- Added more pics/gifs to Milla Jovovich, Samantha Saint, Sharon Lee