First off I wanted to show appreciation for the mod; its awesome and all the effort and work put in is appreciated.

Summary:
The issue I'm having is that Doggy Talents Next causes all textures to appear as black on both 1.20.1 singleplayer and on a multiplayer server if you're playing on an Apple OS with an M1 processor (cant verify outside of that specific processor).

Textures appear all black both with and without the Better Dogs crossover on the Macbook Pro for version 1.20.1. I'm not sure what the cause is because aside from the textures, the game runs fine. I know this because on a server with multiple players the player on mac can play the game crash free but only their textures are all black none of the Windows OS players. Does that mean it's 'client-side based' for lack of a better term? Doggy Talents and Doggy Talents X Better Dogs worked for version 1.19.2 if that is of any help.

Here's a screenshot, hope it helps:

If you need anymore info, please, let me know and I will promptly send logs or whatever I can to help

Thanks :)

Hmmm this is pretty unlikely the problem with DTN....
Have you tried it again without DTN installed or a vanilla client?
We are glad that you appreciated!