I may have mentioned this before, but thought it was worth mentioning again for the newer treg testers if they are having some adjustments problems.
I found two primary issues to deal with, which really led to the same basic problem.
I was used to a flat keyboard. Never used one where the key layout was angled. So, as you may have noticed others comment on, I would miss the pinky key characters a lot.
There were two things I had to work on to minimize this. One was elbow position. My practice had been to have my elbows right at my side, but this pulls the pinky key down - fine for a flat keyboard for me, but magnified the problem I had with the TB angles. Fortunately, my desk chair has somewhat adjustable arms and I could set them so, I could get the angle right by placing my elbows on the arm rest in their lowest position.
Then there was the actual angles. I actually suggested that in future versions that WT make it possible to change the angle (I still like the idea - I'm a big fan of user choice, even if some specific design is supposed to be better). WT doesn't agree with me on this! Amazing!
However, there were things I did along the way before going with WT's pure design. You can adjust the angles a limited amount by putting something between the two blades. I just used a small wadded up piece of paper. Someone else used a tiny screw which was particularly good because it was held in place with the magnets. If you change it to much, the device shuts down. But you can change it enough to make a pretty big difference if this angle is giving you trouble.
I don't do this anymore. Haven't for ages. But I think it was a useful approach to get better results early. Maybe for some it would be best to just adjust to the "proper" position from the start, but you may find this to be a good option. As I got better, I simply reduced the changes I had made.