Your specific camera type isn’t supported out-of-the-box (the X-M1). These lighting conditions (the blue led lights) do need a colour profile that matches your camera otherwise you need to go through al sort of hoops and trouble to fix this specific issue. Having SSF specific data and having turned that into a colour profile for your X-M1 would help tremendously. I’m all but sure you don’t have that info But…
ART and RawTherapee come with the same set of camera/type specific DCP profiles (assuming you use Linux: ART_DIR/dcpprofiles). After I noticed your camera type isn’t among them I experimented a bit with the available FUJIFILM profiles (Color tab → Colour Management → input profile → Custom. Select one of the fuji dcp profiles).
You do need to try out the Tone curve, Base Table and Look table settings as well as the Highlight reconstruction (Exposure tab) settings. RawTherapee gives you the possibility to (un)check Clip out of gamut colours, this option is not available in ART as far as I know.
In the end I used these (RT) settings for the above image as a starting point for my edit:
- Clip out-of-gamut colours → checked
- High light reconstruction → on → Colour Propagation
- Highlight compression → 86 (this setting depends on other factors as well)
- Input profile → FUJUFILM X100S.dcp
- Tone curve → checked
- Base table → unchecked
- Look table → checked
EDIT: Just in case they aren’t on your machine, here’s a zip with all the available fujifilm dcp profiles I have: dcpprofiles.zip (11.2 MB)