I've observed that most species of toads that I've kept over the past 27 years have all done that toe tapping thing, especially when they are lining up to catch food with their tongue. It seems to be an amphibian thing. My one pacman does it too sometimes.
I feed our crickets with potatoes, carrots and greens, and also a commercial cricket food powder. I also dust the crickets for the babies every feeding, but for adults, I dust less often because I've heard that too much is bad, too.
The toad chirping is because he is a male and males have what's known as a release call. When another male mistakes him for a female, the release call is to let that guy know "Hey!Get off me! I'm another boy".
In bad cases of metabolic bone disease, serious muscle twitching can occur but its more extreme than would be seen with the toad tapping the toes thing which usually is only done when they are hunting.
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