Alright gurus, making a long story short, I have a lemon of a CNC, (bought it from Lightning CNC/Cleandrew Smith - big mistake). I've had nothing but issues with it, and I keep tweaking, getting it closer and closer to working well. The latest issue is it starts losing steps in the middle of a job, even easy jobs where it's barely working.

My stepper motors definitely get hot - if I really want to I could probably keep my hands on them, but I'd have to want it. They are NEMA 23 23HS45-4204S (these).
My drivers are DM542A.

I am totally new to this type of electronics, so be prepared to feel like you're talking to a 2 year old...

Can you guys spot something wrong with this setup? Or tell me where to start trouble shooting why this thing is losing steps?

Below are some pictures.

Thanks in advance and I hope you guys can help!