In #4 I suggested that you try the software provided by Open-Smart.
They made the board.
I also offered to help you get the display running with MCUFRIEND_kbv
Your GitHub link refers to a 40-pin display from Inhaos.
Normally 40-pin displays use parallel 8080-16 interface.
The GitHub code is using SPI.
Your Open-Smart board uses 8080-8 interface.
David.