Custom.fx outside folder is must - unless there is allready one in folder you choose.
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Sweetfx.cfg outside folder is - OPTIONAL for all LUTS- (only if you want even more sharped, colorfull and contrasting game).
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If you delete something -there is original reshade 2.0.3. files for backup.

Reshade Version 2.0.3
-----Manual install-----
(download ,unzip and place somewhere on desktop)
open folder RESHADE- ver 2.0.3.1121 
and copy files (reshade folder,reshade fx and reshade64.dll) to
 
"C:\GOG Games\The Witcher 3 Wild Hunt\bin\x64" 
or
"C:\Program Files(X86)\Steam\SteamApps\common\The Witcher 3 Wild Hunt\bin\x64"

rename reshade64.dll to dxgi.dll
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How this works ; 
- you must have a lut.png in reshade/texture folder 
- and name of that same lut.png must be in cfg file

Example:

1. open folder Land of Rivia (from zip you downloaded )
    copy all RIVIA luts (7 png.files-RIVIA1.png,RIVIA2.png,...etc)
    and place them in;
    witcher3/bin/x64/reshade/customfx/texture folder

2. open CustomFX.cfg file (located in Reshade folder) 
    with  notepad and find line in 
     //>Color LUT Settings<\\;

write the name of texture(lut)
#define TuningColorLUTDstTexture "RIVIA1.png"

SAVE that CustomFX file. 

How to change luts ;
(to simply swap the names of color luts, while in game, alt-tab and add different number,
before you start the game open CustomFX.cfg

#define TuningColorLUTDstTexture "RIVIA2.png" 

and save again.
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As you can see by number of folders this was not 5 min Job, 
(not saying my luts are perfect)
but please, credit me if you use lut-s in your presets
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