Here's a link that may help you out with the dog/bunny introductions! Actually I recommend rabbit.org for just about any bun related information, it's been a life saver for me!

http://www.rabbit.org/journal/1/dogs.html

Check out the section on diet too, no idea how pellets compare with the rodent blocks, but I do know an unlimited supply of timothy hay is a must to ensure a long life with no hairballs or dangerous blockages. Bunny impaction is bad. I've also learned the hard way that green lettuce = good treat and iceburg lettuce = loose nasty stools and gas. That was not fun. So yeah, very helpful tips on that site to avoid nasty surprises like that!

They're a blast to have roaming around the home. Death by cute. We'd like to get a Holland Lop eventually too, but I think 4 buns is my limit for litter box duty, lol!