The change in format is noticeable with Saxon, but it can be tweaked. I would work hard to restore her confidence as math grows more and more challenging. (I'm not one for switching, but if you know Saxon would be a good fit for her, I say go for it.)
Possible suggestions for Saxon or any program
The Warm UP is similar to the meeting book, but shorter.
Work with her or use the DIVE or SaxonTeacher cd rom.
Take longer to complete the lesson, two days or less of the practice sets problems. (I'm ducking the tomatoes, but it does work for some students.)
Write in the book to avoid copy-work mistakes and frustrations.