I took a lot of time to improve the washed out look of the game.
It's not perfect, because I'm not a specialist in these things.
I also adjusted the colors a bit and added some Bloom. If this bothers anyone, just disable the Bloom and Technicolor filters.
I also play the game in 1024x768 resolution in 4:3.
For this I use the tool "Res-o-matic" (RESO7.EXE), surely there are more modern tools but I am very satisfied with this old tool.
https://www.bcheck.net/apps/reso.htm
The game is started for this purpose with the following command.
"...\reso7.exe" "...\GOG Games\Broken Sword DC\bs1dc.exe" 1024 768 32 60

• To improve the sharpness first download Reshade (I used version 5.9.2).
https://reshade.me/#download

• Start Reshade and select the game directory.
• Install the OpenGL shaders as suggested by Reshade.
• Creates the file ReShadePreset.ini and copies it into game directory.
• Start the Game and press Home key, Skip the tutorial, activate the Performance Mode and press Home key again.

ReShadePreset.ini
________________________________________________________________________________________________________

KeyPCGI_One@RadiantGI.fx=46,1,0,0
Techniques=AdaptiveSharpen@AdaptiveSharpen.fx,LumaSharpen@LumaSharpen.fx,Mode1@FineSharp.fx,PPFXBloom@PPFX_Blo om.fx,Technicolor@Technicolor.fx,Clarity@Clarity.fx,Directionally_Localized_Anti_Aliasing_Plus@DLAA_Plus.fx
TechniqueSorting=AdaptiveSharpen@AdaptiveSharpen.fx,LumaSharpen@LumaSharpen.fx,Mode1@FineSharp.fx,PPFXBloom@PP FX_Bloom.fx,Technicolor@Technicolor.fx,Clarity@Clarity.fx,Directionally_Localized_Anti_Aliasing_Plus@DLAA_Plus .fx,Daltonize@Daltonize.fx,Deband@Deband.fx,DisplayDepth@DisplayDepth.fx,LUT@LUT.fx,Mode2@FineSharp.fx,Mode3@F ineSharp.fx,UIMask_Top@UIMask.fx,UIMask_Bottom@UIMask.fx

[AdaptiveSharpen.fx]
curveslope=0.500000
curve_height=0.750000
D_compr_high=0.500000
D_compr_low=0.250000
D_overshoot=0.009000
L_compr_high=0.334000
L_compr_low=0.167000
L_overshoot=0.003000
pm_p=0.700000
scale_cs=0.056000
scale_lim=0.100000

[Clarity.fx]
ClarityBlendIfDark=50
ClarityBlendIfLight=205
ClarityBlendMode=1
ClarityDarkIntensity=0.400000
ClarityLightIntensity=0.000000
ClarityOffset=2.000000
ClarityRadius=2
ClarityStrength=0.400000
ClarityViewBlendIfMask=0
ClarityViewMask=0

[DLAA_Plus.fx]
De_Artifact=0.000000
Long_Edge_Mask_H=0.000000
Long_Edge_Mask_V=0.000000
Short_Edge_Mask=0.050000
Text_Preservation=0.900000
View_Mode=0

[FineSharp.fx]
cstr=0.900000
lstr=1.490000
pstr=1.272000
sstr=2.000000
xrep=0.250000
xstr=0.190000

[LumaSharpen.fx]
offset_bias=1.000000
pattern=1
sharp_clamp=0.035000
sharp_strength=0.535000
show_sharpen=0

[PPFX_Bloom.fx]
pBloomBlendMode=0
pBloomCurve=1.290000
pBloomIntensity=0.800000
pBloomRadius=64.000000
pBloomSaturation=0.600000
pBloomThreshold=0.827000
pEnableHDR=0
pEnableLensdirt=0
pLensdirtCurve=1.200000
pLensdirtIntensity=1.000000
pTonemapContrast=1.020000
pTonemapCurve=3.000000
pTonemapExposure=1.200000
pTonemapMode=0
pTonemapSaturateBlacks=0.000000

[Technicolor.fx]
Power=4.700000
RGBNegativeAmount=0.880000,0.880000,0.880000
Strength=0.160000