Harold 1040 Frames Sticking

I just purchased a 4 frame, 6 treadle Harold 1040, but the frames get stuck about every other time I use them, especially frame 2. I completely cleaned it up, lamb mechanism and all. What oil should I use on the metal lamb mechanism? What lubricant on the wooden frame shafts? 

Also, the wing nuts for tightening the back warp don't tighten enough, so I will need to look into that.

I am thinking of adding a friction brake to the back warp. I will design it myself, unless there is a simple solution already out there.

 Thanks in advance for your help.