Nodgree is the actual face changing or just the hair and clothes?  If it is just the hair & clothes I can help!  What is happening is you have not set the hair for all the outfits to the same thing.  I am going to go out on a limb and guess you have Seasons, BV and/or  FT installed.  (If not this isn't going to fix it, but I have had this problem before I realized it was ep related confusion.)  Here's how to "fix" this:

1) When your in CAS go to the 3rd section down from the top (changing the eyes/hair/face/general tweaking area) and go to the hair section.  Look at the outfit selector in the upper left corner of the tab and go to the everyday outfit (if the selection for all is green and the outfits are grayed out, UNclick it, and  select the everyday outfit).   Now click on the hairstyle you want your sim to have all the time.  FINAL STEP -- click the top outfit selector (the all outfit/ one with the sideways figure 8 ).  This should gray out the other options and the hair should stay the same for all your outfits now.  

As to why the other outfits aren't what you thought they would be -- you do realize that when building in BS you can only save one outfit on a sim (be it formal, undies, swim wear, nightclothes, everyday, OR outerwear) and that you have to pick one to upload your sim in and then select the outfits for all the other occasions in CAS, right?  The other issue you may be having is CC that doesn't display properly in-game.  Then the game just picks the first (usually hideous) outfit it sees in line that is EA created.  


Hope this resolves the issue for you!

Yesterday, I installed Seasons on my computer. My game had worked fine until then, but when I tried to play Seasons, the old "The application has crashed. The appliaction will now terminate." message popped up, halfway through loading Riverblossom Hills. I'd had this problem before, so I removed all my custom content and tried again. The same message appeared. Before, when I've had this problem, it was because of a piece of custom content that was conflicting with the game. Once I removed that file, the game worked. This time, though, it obviously wasn't a conflicting file. I know lots of people have had this problem, but I haven't found any "cure" for it yet. Does anyone have any suggestions?

If that is something that worries you what you can is:
1) Start up your game and once one of your neighborhoods has loaded open your cheat console and enter "boolprop testingcheatsenabled true" (without the quote marks).
2) Next start up the Create A Family. When you go to the clothing section you will notice that with this cheat enabled when you hover a clothing icon its package name appears. Note down the package names of the clothes that don't work.
3) Close your game and then go to your downloads folder. Remove (dont delete yet!) All the packages that you noted down. You should have removed all the clothes that don't work.
4) Restart your game and check to see if any other clothing has been affected. If it hasn't, it's safe to delete those files you moved If it has, you'll have to go through a trial and error process of putting one mesh at a time back into the game and seeing which mesh you were missing.

I hope that works for you

do you have pictures of what's happening?

After you finished to create a sim in Body Shop, you have to close the window, and now you have to choose from the main menu (the window of "create a sim") the option: "package a sim", click on your newly created sim, and confirm the package. The packaged sim file will appear on your desktop.

Double-click on your desktop packaged file, and order "install". It will be installed as it is now, and you will find it's new appereance in CAS.