I cant install this shader phosphor21x

[8bit_astronaut]

I tried everything, but i cant install the shader phosphor21x that appears here [link](http://filthypants.blogspot.cl/2011/05/more-emulator-pixel-shaders-crt-updated.html?m=0 url)
I followed the guide in the wiki, but the file tipes looks weird, also, it says its compatible with retroarch so....please if someone could help me, that would be great.

Pd: for the recalbox developers, it would be a great shader to add in a new recalbox version in the future