Try using Ronsonol lighter fluid on the stone. I have been using it for about 15 years. Tends to leave the grain on the stone open and will cut better(the steel). You'll need to wipe it off a little more often and keep adding fluid, but it works great. Sounds like you need reduce the angle. I sharpen at about 5 degrees, very flat. This will ruduce the sharp hump you get from the steeper angle, tends to glide through the leather better. Also, strop the heck out of it as soon as the burr falls of when sharpening on the stone. Use a white chrome rouge, green rouge, or others are available. White tends to stick better to a piece of leather because it has more grease in it. you may also use valve grinding compound, available at NAPA or Carquest stores, get a fine grit(500 or 600).
I use a ceramic stone from Spyderco, but the stone you are using is fine. Don't worry about using the fine stone(white), use the medium then strop the knife. You should be able to get a lot of use out of the knife, if it is a good one, just by stropping it.
I also use UHMW for a cutting board. This is usually the stuff you find for kitchen cutting boards. Pretty easy on the edge.
Good luck.