New to CNC Laser Engravers and having some issues.

I recently bought a 40"x40" 15W laser machine from a Chinese manufacturer. It's been nothing but a headache. I'm familiar with vector software so and I've been learning using Lightburn for the Laser. The first problem I ran into was a bad laser driver that came with the machine that constantly told the laser to stay on. After about a month communicating with their "tech support" I was shipped a new one and that fixed that problem. My new problem is with the the lines it's engraving. I plan to primarily use this on wood to put designs on cornhole boards and the like. I'll also be using it for stenciling for some wood working projects as well. I've uploaded some images of what's going on. You'll notice that the letters have really wavy lines in them and that the bottom right corner of the squares are not closing. I have taken the time to try and calibrate the axis within the Lightburn software. Again, I'm new to all this so bear with me. Luckily I'm pretty good at picking things up so hopefully it won't be too much of a headache if someone is willing to give me some pointers!