RE: lag bolt steps
I've made a few of my own before out of 4x5 angle. The heads will pop off those lag bolts though after they have been in the tree a while. Luckily I learned it close to the ground. I don't use those type any more.
I tie them on with rope now. I've got some that have been hanging on the tree for four years now and I climbe it today as easy as the first day I tied them on.