Hi! I have a problem with gbc slang shaders: gbc-2x and gbc-3x look identical, and gbc-4x, gbc-5x and gbc-6x look identical (the scaling should change but it looks exactly the same).
Same problem with the gba shader, except that the game is also zoomed in on the LCD screen (see screenshot).
I’ve used the GLSLP versions of those shaders and they looked fine.