Sir Draconion said:
uh! just a thought
416 equals 11
4 of one
1 of another
and 6 of the last
I think Sir Draconion has the basis of the solution here. If there is no "punishment" for putting the wrong blocks in the space, I would try all the combinations using 4, 1 and 6 of the different types of blocks.
My guess for the correct solution would be 4 Shields, 1 Dragon and 6 Swords.
First, that's the order the description lists them (yes, cheesy).
Second, the proverb beings with three main sections:
"For they sleep not"
"Except they have done mischief"
"And their sleep is taken away"
I would associate the first with the shield, as defenders must not sleep.
I would associate the second with the dragon, as they do mischief.
I would associate the third with the sword, as it can take away someone's "sleep"
Of course, with different interpretations, those could be flipped around (someone with a sword could be up to mischief as well), but those seem to fit the best that way.
As for the final bit of the proverb "unless they cause some to fall". It may be a warning not to allow the corpse to fall. I'm not sure.
Just an idea to try!