I see these a lot and I have a possibility for you to consider. I assume in answering that you're as yet uncertain about what attribute levels will and won't pertain by the time of product launch so that you're using CBC to test multiple levels of multiple attributes.
One thing I often do in these kinds of studies is to ask two standard, 5-point scale, purchase intent ratings questions about the new product, one for a well-featured version of the new product and one for a relatively impoverished version of the new product. You can simulate shares for the new product using your CBC utilities, of course. You can also apply some common deflators of purchase intent overstatement. This gives you a target to use in calibrating your CBC utilities - in fact, you now have deflated purchase intent for both strong and weak versions of the new product to use in your calibration/data fusion.
There are some other things I often do in these kinds of studies, but it sounds like you're already planning those. Good luck.