That is definitely a metaphor :)
The lines that use a simile in this excerpt are "Thus while he spoke the blue-eyed maid began With pleasing smiles to view the godlike man" as it compares the maid's actions to a simile.
Metaphor
Yes, there is a simile in "Chasing Vermeer" by Blue Balliett. An example of a simile from the book is "Blue as a bruise" used to describe a character's eyes.
As blue as the oceans depths
Blue can be used metaphorically to represent feelings of sadness or melancholy, as in "feeling blue," but it does not inherently function as a metaphor without context.
Eyes as blue as saphires
The buttons are BLUE!
Blue Boy Bachelor's Buttons grow three feet tall.
Yes
as blue as sea
No. If anything that is an idiom. A simile is a comparison of two things using words like "like" or "as". An example of a simile is "Her eyes are as blue as the sky".
Which tiny blue button are you searching for? There are several 'tiny, blue buttons' on iMovie. Open the program and you will see that Start, Preview etc, all have tiny blue buttons.