I suggest you use what is on thingiverse as well. You just happen to want to start right as I have the first major update in a year planned. I am updating the docs and all the various pages this week. The updated part are the center and z axis. So if you want to start with the corners and rollers the new center parts should be up today or tomorrow.
Everything is done now except the assembly instructions for the middle assembly. I will be working on that today, hopefully done tonight if not tomorrow.
I know it is slightly confusing but better parts are worth it right?