Integrating a Custom 32 Bit Board in Marlin 2.0

I'm working on a board from Ultimachine and you can access the Marlin files here.

The printer is a modified Gigabot from re:3D. The current configuration of the printer is one X, 2 Y, and 2 Z steppers, same for the endstops, dual extruders, and it uses a RepRapDiscount full graphic smart controller

When compiling the firmware directly after downloading with no changes I have no issues. When I enable dual steppers I get an error like "No E stepper plug left for Y2!" and "Y_DUAL_STEPPER_DRIVERS requires Y2 pins (and an extra E plug)."
even though there's 3 additional spots that it says it should automatically fill the next available extruder. Even if I go through and change the E stepper defines to Y2 and Z2 I still get the same errors. I fell down a rabbit hole yesterday trying to track the issue but I felt like every time I "fixed" something it broke something else.

This morning I tried taking the pin file for this board and moving it to the latest release of Marlin 2.0.4 but that wouldn't work for me for other reasons. All I want is this board to give life to the printer even if it's just simply making the bed move up and down.

Any advice would be really appreciated.

Step 1

Identify the motherboard.

The linked marlin is either BOARD_RAMPS_14_RE_ARM_EFB or BOARD_ARCHIMAJOR
The RAMPS_14_RE_ARM_EFB only has 5 stepper drivers, the config has #define EXTRUDERS 2 so there are no free extruders to use as Y2

The BOARD_ARCHIMAJOR seems to have 5 extruders.

This is a real oddball controller, people have been working on adding support for it since 2017...
[github.com]

Quote
Dust
Step 1

Identify the motherboard.

The linked marlin is either BOARD_RAMPS_14_RE_ARM_EFB or BOARD_ARCHIMAJOR
The RAMPS_14_RE_ARM_EFB only has 5 stepper drivers, the config has #define EXTRUDERS 2 so there are no free extruders to use as Y2

The BOARD_ARCHIMAJOR seems to have 5 extruders.

This is a real oddball controller, people have been working on adding support for it since 2017...
[github.com]

Thanks for linking that github thread I have not seen that before I'll probably go down a rabbit hole today of reading through what they've been dealing with.

The board I have is the Archimajor board and it has support for up to 8 stepper motors on the hardware side of things.

@JMS728
I had a similar Problem, in the Pins-File you have to define Pins for X-/Y-/Z-axis and E0 to Ex for the rest of the Stepper-Drivers. If you then enable "X_DUAL_STEPPER_DRIVERS" in configuration_adv.h X2 will be assigned to E1 or E2 depending if you have 1 or 2 Extruders. So you have to have unused E-Drivers.
I hope this will help you.