Tuete:
The simple way is to go to Mask Editor/Button Ediitor and drag the Mask Change operation to the Button Functions window. You can then select which mask you wish to change to.
Now, if you want to change to different masks depending on what the current mask is, you have to use some logic in the circuit diagram. We have done this. If this is what you want to do, post again and maybe I can help.
nOrM