Textures pack does not load

[lkhw]

Hey guys, I am trying to play Muramasa: The Demon Blade but the textures pack does not load.
I am using Macbook Air M1.
I am using Dolphin 5.0-14007.
I have downloaded and unzipped the v1.1b texture pack and put the "RSFE7U" folder inside this folder: "/Users/[my user name]/Library/Application Support/Dolphin/Load/Textures".
In the Graphics menu of Dolphin, I have clicked "Load Custom Textures" and "Prefetch Custom Textures", and have chosen "6x Native (3840x3168) for 4K" as internal resolution.
When I enter the game, although it shows "Custom Textures loaded, 4.0mb in 9.0s", the graphics look like original low resolutions.
In the "Properties" of the game in the Dolphin menu, I note that the game ID is "RSFE7U (0001000052534645)" instead of just "RSFE7U". Not sure if this causes the problem.
I have tried to rename the texture pack folder from "RSFE7U" to "RSFE7U (0001000052534645)", or "RSF". But the problem remains.

Any help is very much appreciated. Thank you!

[JosJuice]

I wonder if maybe the M1 doesn't support the texture formats that Dolphin needs for loading DDS files...? If so, you'll only be able to load PNG. Perhaps the 4 MB of textures that it did manage to load is in PNG format.

Normally this problem only happens on Android devices and such, as basically all PC GPUs support the formats that Dolphin needs, but maybe the M1 is different. I'm not sure.

That Dolphin says the game ID is "RSFE7U (0001000052534645)" is not a problem. The folder should be named either RSFE7U or RSF in that case.

[Miksel12]

This video states that M1 does support Bc 1-7: https://developer.apple.com/videos/play/tech-talks/10859/?time=222