Why would the castors not be the proper colour? Opal is the dilute of castor they are the exact same colour, but insted of DD in the castor it is now dd for opal... All other things are equal.. Lilac is dilute chocolate and is recessive to black so unless you breed to other chocolate carrier it won't be a problem, Chocolate agouti is not showable but Lynx is, which is the chocolate version of opal. So it shouldn't become a big deal, either you sell them or if they have that great of type you breed them to dilutes. There is nothing wrong with your does "colour" pedigree, everything is compatible, in other words you won't get any strange shagouti colours or anything like that lol!