[mark_k]

Like a complete noob I tried making my own shader by simply modifying _winuae.fx, changing filtermode to POINT in the SourceSampler definition:

sampler	SourceSampler = sampler_state {
	Texture	  = (SourceTexture);
	MinFilter = POINT;
	MagFilter = POINT;
	MipFilter = NONE;
	AddressU  = Clamp;
	AddressV  = Clamp;
};

On trying to use that filter with the attached config, starting emulation gives a black screen and this over and over in the log:
D3D9Ex: SetTechnique: 8876086C S=1 F=0876 C=086C (2156) ()

Any idea what I'm doing wrong?