What 'trouble' are you having? Ofna gives out good instructions and the needles are usually set right or are easy to set to get running. Plus Ofna explains the heat cycle method that is proper the tried and true way to break it in.

If it is hard to start, the Hyper .21 needs to be heated with a hair dryer thoroughly before you pull the cord. The piston will always lodge itself in the sleeve until the engine is broken in. If you don't heat the engine thoroughly, you will most certainly snap the pull cord.

You will need some spare glow plugs to survive as well.

Once running, and you shut it down, you must move the piston to the bottom of the stroke (BDC).