Informations
It looks like RSSLO did not have any calibrated screens... Mittenwaldbahn have same flash color issue as Sdbahn and Tauernbahn. I already have this beta fix for the new route.
This fix will patch some Mittenwaldbahn specific vegetation and 1 terrain map.? The file from this fix only affect Mittenwaldbahn. 


Install
You need to first install Sdbahn & Tauernbahn : no more flashy vegetation. The 9 first files are required to fix any RSSLO routes, they are common to Sdbahn, Tauernbahn and Mittenwaldbahn

Files to backup :
Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Grass\Grass_01.TgPcDx
Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Grass\Grass_02.TgPcDx
Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Grass\Grass_03.TgPcDx
Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Grass\Grass_04.TgPcDx
Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Grass\Grass_07.TgPcDx
Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Grass\Grass_08.TgPcDx
?Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Textures2\Weeds_01.TgPcDx
Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Textures2\Weeds_02.TgPcDx
Assets\RSSLO_Routes\RSSLO\scenery\Vegetation\Textures\Textures2\Weeds_03.TgPcDx
Assets\RSSLO_Routes\RSSLO_Karwendelbahn\Environment\Terrain\Flowers04\Flowers04_A.TgPcDx
Assets\RSSLO_Routes\RSSLO_Karwendelbahn\Environment\Terrain\Flowers04\Flowers04_B.TgPcDx
Assets\RSSLO_Routes\RSSLO_Karwendelbahn\Environment\Terrain\Flowers04\Flowers04_C.TgPcDx
Assets\RSSLO_Routes\RSSLO_Karwendelbahn\Environment\Terrain\Flowers04\Flowers04_D.TgPcDx
Assets\RSSLO_Routes\RSSLO_Karwendelbahn\Environment\Terrain\Flowers04\Flowers04_E.TgPcDx
Assets\RSSLO_Routes\RSSLO_Karwendelbahn\Environment\Terrain\Flowers04\Flowers04_F.TgPcDx
Assets\RSSLO_Routes\RSSLO_Karwendelbahn\Environment\Terrain\Flowers04\Flowers04_G.TgPcDx
Assets\RSSLO_Routes\RSSLO_Karwendelbahn\Environment\Terrain\Flowers04\Flowers04_H.TgPcDx

Extract the downloaded 7z file
Use the rwp to install the
or
extract the file from rwp and copy the assets extracted folder your railworks assets folder.


Uninstall
Restore your backup file


Issue
None, it's the original RSSLO texture with some color adjustment.
Changing one route affect sometimes other RSSLO routes...