A few things to bear in mind:
You really have to gyrate your shoulders and knees to get them out of the way when doing the btb weaves.
Heavier wicks are easier for these moves, IMHO. It is hard for you to exert a lot of force in the btb position, so the extra momentum helps carry them around. By the same reasoning, you need a certain amount of speed. That makes it harder to learn, since you can't slow the motion way down, but it's the only way to get the wicks to swing clear of your body.
Turns are tricky. Although I can do both fwd and rvs btb weaves (for some reason, I find the rvs easier), turning is still a problem. There are four possible turns--left or right, and starting fwd or rvs. So far I only can manage one of these--starting rvs, turning right (and for whatever it's worth, I'm a leftie). I'm whacking myself silly trying to get at least one more turn (right now I'm focusing on right turn starting fwd). I find that I really have to concentrate on what my hands are doing, figure out where they need to be, and consciously force them to be there. Eventually it all becomes instinct, but until then, you (or at least I) have to concentrate on what you're doing. I've almost got it, but I keep getting hung up.
Pay attention to what your hands are doing with normal in-front turns, where they end up and that sort of thing, and try to carry that over to btb turns.
Keep at it--if I can manage it, anyone can.