Been forced to put down the soap for the past few weeks -- I'm having withdrawal!

But now that some of my first batches are being tested by myself and some cheerful volunteers, I've got a question about texture

With one of my recipes, the finished bar, when first used, sticks to the skin a bit. I don't find that it leaves the skin sticky or anything, but it's hard to actually use the bar at first, it sticks so much! It doesn't glide over wet skin as one might expect soap to do. After a little persistent use, it seems fine, though, almost as if some layer had to be removed from it. Is there something in the recipe causing this? And/or can I counter it with something else? Or maybe the soap just needs to cure longer? It was at ~2 weeks when I used it (I'm impatient, and the water's at 30% ;D) but ~4 when other folks tested, and I still got a comment about the stick. Here's the recipe:
Coconut Oil 28%
Palm Oil 20%
Olive Oil 30% (half of this was infused with comfrey leaves for color)
Shea Butter 8%
Castor Oil 14%
1 tbsp honey PPO
approx. 1 gram of goat's milk powder per 1 oz of oils
SF: 6%
Looking at it, I suspect it may be the castor oil, but... but I need lather!
On a side note, I made an oatmeal soap with the same base (minus all the comfrey infusion, plus some ground oatmeal), and it doesn't stick at all -- but I've noticed that oatmeal makes for a very nice lathery soap, which may make a difference?
Possibly related question: what exactly IS
slip? I see it mentioned with virtually every shaving soap and almost every comment about using clay, but I can't find what it actually means anywhere. My first thought was that it meant the slipperiness that soap can leave on your skin, but somewhere or other, I saw it used in such a way that it almost sounded like the opposite.

Help?