My beardie didn't eat a thing for like 10 days+ when I first got him, no crickets or greens, I was really freaked out too. I had the same issue with the crickets just hiding too well, so went to a small fish tank for feeding and he gradually started eating and is fine now. Also worth noting though that mine was a bit older at this stage - about 7 months.
Just make sure it is warm enough and it has a decent basking spot (I think that was part of my problem). I'm far from an expert, and it's probably a coincidence, but mine started eating the day after he had a big drink of water, so maybe give it a bit of a spray with some water - probably a good idea if they aren't eating much at the moment anyway.
Are you keeping them separate when you try them in the smaller container with the food? Or both in at once?
Also I think the glass surfing stuff is just part of settling in, mine did it a lot too (he even fell asleep in a vertical position up against the glass once, was cute but sad
). Mine still does it occasionally, but no where near as much.
