yes, the velveteen lop was hard to create. they are a 6 pound lop with rex fur.
it order to create the velveteen lop, mini rex were bred with english lop. this breeding created F1 rex carrier velveteen lop hybrids (wow is that a mouthful! ). if you take the rex carriers and bred them to another rex carrier you have a 25% chance of getting rex babies. if you bred a rex carrier to a rex coated rabbit you have a 50% chance of getting rex coat. and if you bred a rex carrier to a normal fur rabbit that doesn't carry rex, you won't get rex fur, but you *might* get a rex carrier.
the same with satin coats, and i *think* the same with angora coats, but i could be wrong with the angora as i never really studied that gene as i never worked with it when i bred (we bred mini rex, and almost got into satins, so i know about them)
hope that wasn't to confusing, and sorry for getting off-topic!