To fix the RWR issues under Proton/Wine:
you had to open:
Mods/aircraft/F-16C/Cockpit/IndicationResources/RWR/font_RWR.tga
Mods/aircraft/F-16C/Cockpit/IndicationResources/RWR/indication_RWR.tga
in Gimp and save them again. This worked great in DCS 2.7, but in DCS 2.8 this now leads to a tainted state and you cannot use multiplayer anymore. I wonder if you could exclude these textures from the integrity check or if you could even use the updated textures?