I was just at my sister's house and they had some great looking new custom
cabinets with flat panel doors made by a local guy -- except in a door on a
large pantry cabinet the panel had moved and I could see unfinished areas
on the panel.

Is there a trick to staining/finishing the panel so when it moves around
you don't see any unfinished surface? Do you finish the panel before
assembly -- or, at least stain it first?

I ask because some cabinet doors are on my todo list. Thanks.