Like others said, you should consider a nest box. I know very little about breeding rabbits in particular, but you have a few things going on there that are issues no matter what the species is. (I've raised and fostered everything from squirrels to cougars, geckos to cobras. Animal behavior is also a favorite subject of independant learning for me))
A) they are exposed on all sides. This makes them vulnerable to temperature changes and drafts. It may also make the mother nervous, as they are a naturally "denning" animal, and she may not do as well in rearing them. Argument for a nest box. lol
B) you have them on a folded towel. You should never use folded/excessive towels or blankets as bedding for newborn animals. A baby could accidently get lost between layers or folds and be smothered or squashed. A single, flat towel or small blanket is *usually* fine, as long as they cant get lost in it. (*On second look I see in the lower pic they seem to be off the towel, so if that's a permanent rearrangement, please dissregard this suggestion.
C) The cardboard with which you've lined the bottom of the crate is a good idea, however, you need to move it to the inside of the crate. As it is now, a kit could easily slip a head or other body part through those bars and become tangled or trapped between the wire and the cardboard. This is a great way to end up with accidentally broken limbs/necks/skulls, especially if mom accidently pushes/presses any kits up against the wires while trying to clean or feed them.
All those saying that the whole "mother will eat the babies if you touch them" thing is a myth are absolutely correct. However, the myth (which has been applied to all manner of animals from hampsters to birds) is based in very real fact, the cause is just misinterpreted.
A lot of infanticide in animals is caused by stress to the mother. Many, many things can cause stress in animals, and stress in animals is generally MUCH different than stress in humans. An animal that feels unsafe for whatever reason may become stressed, as well as animals that have undergone a life change, are on poor diets, and a vast plethora of other reasons. Individuals will have different levels of tolerance as to what they can handle without feeling stressed. This is why some animals do fine when people handle their babies and some do not. It has nothing to do with human smell, and everything to do with that individual animal's stress vs.comfort level.
If the animal is stressed in general, say by a recent life change (new cage, new home, etc) then having it's babies handled may stress it out more, pushing it over that edge. If an animal just plain doesn't trust/like you, even if nothing has changed recently, then your handling her offspring could cause enough stress.
In fact, it has very little to do with the actual touching of the offspring itself. It's more the stress of having someone pestering them invaseively at what for that individual animal might be a very frightening and stressful time.
This is also why it's more common with young and/or 1st time mothers (in every species). Enexperienced mothers are easier to stress at this time than those that have been through it before a time or two and know the ropes.