Pulling more fur, she's just being a good mom and making sure they stay warm enough. Or you have more on the way(rabbits have two uterine horns)
As long as she isn't hurting them or laying on them, and they stay snuggled in their nest or with each other right around the nest(don't get separated too far), and don't pester her for milk constantly, I can't see it being a problem.
There may be a few possible issues to watch out for with not having a nesting box. The babies could wander out of the nest, get separated, and get chilled. Also there won't be a barrier to stop the babies from constantly going after mom for milk. But as long as she uses that shelf to get away from the babies if they try and bug her for milk before it's nursing time, that solves that.
So there's just watching for babies getting separated from the nest and not being able to get back. If it keeps happening, then you may need to consider adding a nesting box or some sort of barrier to keep the kits in the nest spot, so none get separated and chilled. Or you can just check on them several times a day and return any that do get separated, back to the nest.
There's also keeping the nesting area relatively clean. If the nest area gets soiled, clean out the soiled part and replace with clean bedding/hay. This will also help prevent nest box eye when the babies eyes start to open. But if mom is using the nest area for a toilet, you may need to consider making more changes.
You do want to check the babies, both new and older ones, every day, a couple of times a day. The new kits you want to check for full bellies or if they appear dehydrated and wrinkly(not fed). Also ones with bellies that might be abnormally distended if mom isn't stimulating to urinate. And check and remove any that might have passed, as a dead kit in the nest will chill the other babies and attract disease. The older kits need to be checked for body condition(feeling too boney, possible health issue) and their bums need to be checked for mushy poop stuck over their anal opening, which is especially a risk with babies that had to be weaned early.
https://flashsplace.webs.com/accidentallitters.htm
With the babies that are weaned early, biggest thing for them is having a sensitive digestive tract, particularly to carbs and sugars, and the risk of weaning enteritis. So limiting or not feeding sugary/high carb foods, and always providing free fed grass hay. Good quality grass hay(no mold, no noxious weeds) is the best thing for a rabbits digestive tracts microflora to stay in balance.
And monitor for mushy poop(cecotropes, not the fecal poop) in any of them. If any have it, it means there is a potential diet and health issue that needs correcting right away. Mushy cecals is different than diarrhea. Mushy cecals can usually be corrected with diet changes to a higher fiber diet. True diarrhea of the fecal poop, is an emergency.
Medirabbit: detailed explanation of the importance of mother rabbits milk
(WARNING: VERY GRAPHIC NECROPSY PHOTOS, but good explanation of how weaning diarrhea can occur in baby rabbits, so if you view, view with caution)
Medirabbit: weaning diarrhea
(note: home remedies for diarrhea are not a replacement for the proper and immediate, veterinary treatment)
