Stauf Puzzle (Painting Gallery)

There's really no way to give a straight solution to this puzzle, since
the initial conditions are randomly generated.

This puzzle is very similar to the crypt puzzle.  If you remember how you
finished the crypt puzzle, you may want to apply your strategies from that
puzzle to this one.

I found that it was best to work one square or group of squares at a time
at the start of the puzzle, until I reached some kind of recognizable pattern
or order to the colors of the squares.  Trial and error is the only real
strategy here, at least when you start out.

But if the above technique doesn't work for you, there is a definite
solution that will get you to the end.  I should warn you first that the
solution I'm about to give is probably the *least* efficient.  The only
advantage it has is that it's guaranteed to work.  I recommend you try to
get to the end and turn only to these hints when you're hopelessly stuck.