Along manshu's path, there are
Non-white pixels, of the following colors:
496d79 7a7661 767221 426769 6e6573 776670 724161 7a7767 6f6d64 2e4275 736371 676763 6d7a74 627163 667072 726761 7a7667 676762 2e4262 646b62 757366 2c6f69 616d67 677a72 6f7666 70726f 666565 72662e
Using the obvious hex-to-ASCII conversion, we get
It obviously isn't a coincidence it's a bunch of letters and punctuation, so perhaps we have a Vigenere now.
As Wu33o pointed out in comments, the key to the Vigenere is
Which gives the message
Well done! Now free the Minotaur. The key to unlock the door is out. Only then, can you read the answer.
That "key" in hex, is
6f 75 74
The numbers manshu found are the colors
So, using the relevant number
and taking every 25th letter of the boxed text in the question, we get the word