I have the YL600-2S-2K20 P 110V VFD. I have configured it for using an external source to control the run. According to the enclosed documentation to set to forward run it shows using the X4 terminal

If the spindle runs in the opposite direction than what the VFD shows in the indicator (also when X4 and X5 terminals are used) that sounds like your three wires going to the spindle are incorrect. All you need to do is switch two of the wires and your spindle will run in the correct direction. Additional Information: I am still waiting for the cable to connect my spindle so that doesn't come into play yet. I am just looking at the results of the led indicators as being reversed of what the documentation says that I should get by using the X$ and X5 terminals.