The sample problem I kind of gave up on and guessed sort of... it couldn't be sorted by color that's too obvious.

And then the real problem number 1. The answer is "Left - each figure contains an even number of arrow heads. Right - each figure contains an odd number of arrow heads"... but on the right I can clearly see that the three eggs across the top have an even number of arrowheads.

It's not the number of arrowheads on the egg; it's the number of arrowheads on each of the little figures on the egg. Those eggs you mention have 2 figures each, true, but each figure has just 1 arrowhead each.