You just need practice. Once you get the hang of it, you won't understand why you had trouble to begin with. The biggest problems you will have; extremely shallow targets can pinpoint almost anywhere along the center. If you have a shallow target, turn the coil 90 degrees and you will get an "x marks the spot". Angled targets throw off the pinpoint to the side, but you shouldn't be digging tiny plugs anyway. If you have an empty hole this is where a pinpointer works best. If I still don't get a hit in the side of the hole with the pinpointer, I use my digger and widen the bottom half of the hole by a couple inches and try the pinpointer again. Lastly, on-edge coins with give a target on both sides. there have been many time I get 2 empty hole a few inches apart and find a coin in the middle..
Keep using your CTX, it gets easier.
Keep using your CTX, it gets easier.