SO what im guessing you are trying to do is make it so that the message box shows the face of the class you choose at the start? Its really simple. After choosing a certain class, change a variable to a different number for each class.
So if you choose class 1, change variable 1 to the number 1.
If you choose class 2, change the variable to 2.
Now, for the message, setup a conditional branch. If Variable 1 is equal to 1.
Inside that condition, change the face for the message with "face graphics".
Also put the message inside the conditional branch.
Anything else you want to happen specifically for class 1 should also go into the branch.
Make a new conditional branch for each other class with the same stuff inside.