@kdaffy If you use dynamic laser power that may solve the dark edges, in T2Laser you can enable it in the menu.

The laser module (which is really a 3.5W) may have poor current control which is causing the issue, if it surges at startup you would get the dark edges and it can't be fixed in software or firmware.

@kdaffy You can increase to 8000 mm/min feed rate without any issues on most machines, and it is possible to go even faster if the axis is well adjusted (belts are correct tension and minimal friction). The fastest is around 12000 mm/min. Acceleration can also be increased but too much on either setting will cause lost steps and positional issues especially when raster scanning due to the mass changing direction.

@Conqueror Yes but it is not recommended as the drivers could overheat, if you want to do this add heat sinks to the drivers and a small fan to keep them cool. In T2Laser you enable the Hold Position feature and will see the warning message.

@hunter2379 The piece that is broken is an Arduino Nano clone, you don't need to replace the entire control board with the stepper drivers, just get a replacement Nano clone from banggood or ebay, they are $5 or less.

It is plug-and-play, very easy to swap and then load the firmware (very easy to do using T2Laser) and then you can use the machine again.

@kdaffy What firmware are you using? The homing direction can be changed by changing Grbl parameter $23.

@killrob If you compile Grbl 1.1f with CoreXY using Arduino IDE, you can upload to the Nano. You should use OptiBoot to ensure it will fit in the available memory.

@siddhesh-chavan It is usually due to power saving, make sure it is disabled on the USB port and hub.

@Guido-Quaglia Try T2Laser, you'll find it much easier and it comes with firmware already setup for your machine to get the best performance. In the future you can add upgrades like home switches, rotary axis or Z-axis.

@Charles00431 The problem is the firmware, if you use T2Laser with Grbl 1.1e DEFAULT everything will work correctly and you will get much better performance from your machine. I offer full support.

@spawnreaper It is due to the firmware, you have it setup as CoreXY and it needs to be Cartesian coordinates. I don't know how to fix it with Elekscam but in T2Laser you can either load Grbl 1.1e DEFAULT or use the Configure Eleks Mana menu.