I am a fairly new rider and I've got the Terry Butterfly seat that came with my Terry bike. I find I have to tilt it down one notch to keep from getting numb, but other than that once I set the seat height, etc. properly, I didn't have any more trouble. I also move my butt around every so often to give my body a change of pace. I'm going to try the new butterfly gel seat to see if that gives more comfort in the crotch area, as I am still getting used to riding longer distances, and sometimes feel a little "bruised" in sensitive anatomy from being on a firm seat, but have heard seats with gel in them can cause problems from compression. So a seat with gel inserts may not be the answer either. More time training in the saddle probably is.
Most bike shops give excellent service, and it sounds as though yours has tried very hard to please you, but sometimes you have to experiment a little bit by yourself (make one small change at a time) because our bodies do not always follow a standard "norm" that shops go by.Books, bike shops, etc. only give a starting point to work from. Your body will tell you what you need, but again, only one small change at a time. Try adjusting your seat yourself bit by bit and see if that helps.
It may also be that the Butterfly just will not work for you. Talk to the folks at Terry. They are wonderful people and will most likely be able to suggest a different saddle for you to try. They have excellent cusrtomer service, and a good money back satisfaction guarantee.