Custom 2k21 loading screen

[AutoClubMonaco]

Hi guys, i want to make my own 2k21 loading screens but i'm struggling to get a picture to look right or work at all (game crash/black screen/oversized image). Does anyone have a tutorial on how to make one or can provide some info (best program to use and how to save the image in the correct format/mipmpas etc?


Cheers.