Cura is G-Code sandbox but it is quite useless in many scenarios because you won’t be able to see what the printer says in response. This is possible with Prontoface.
So if you suspect that one or more of your sliders, feeder, or hot-end are not working, you might want to take individual control over each unit and control them individually. Prontoface (PrinerRun) lets you do it more easily. Get if from Pronterface Website and set it up using the steps defined in the second half of the following article:
https://all3dp.com/2/printrun-a-beginner-s-tutorial/
The parameters for Markhor3D D7500 are:
Baud rate: 250000
Bed Size: 150x150x140
COM: You gotta see it in your device manager. Look for Silicon Labs UART Bridge in communication devices.
Onec setup, here is a wonderful video that tells you the basics of the interface and even tells you some really advanced but cool features.
It is important that you also tell prontoface the printer dimensions. In Prontoface setting.
So you can control the speed of movement of individual sliders and command them to move in a particaular direction quite easily.
Most of the features that you need are already here on the GUI
Movement (The joypad)
Homing (Home Icons)
Speed Control (Top of the panel)
Hotend Control
Extruder Pull and Push with controlled speed and extent
Turn off all motors
So once you know that you can manually send G commands using Prontoface, here are some common commands that you can send to diagnose your printer. A complete list of commands can be found here.
https://marlinfw.org/docs/gcode/G000-G001.html. You must have already figured it out, but all the GUI does is send these commands that you can already send manually but a lot more easily. Infact, the whole print is based on these movement commands. Lets talk about that some other day!