Not completely sure I understand your problem, but I'll try to help anyway!
If you're on a layout and wish to go back to a previous layout, your solution should work fine! If you are on your start page, then you'll need to change 'Go to layout' to 'Quit'.
One more thing to look out for, is using back button to close any pop-up windows (not sure if this applies to you). We failed Win Phone cert on our first try, as I'd forgotten to allow back button to close a pop-up window in our game (Doh!)
Hope that helps!
If this was not the answer you're looking for (whoa! star wars flashback) please let me know, and I'll try to help you further.
Could also be useful to post a capx, if you are finding it difficult to express your problem!