In 40k DoW SS, using the Unification mods, most of my UI is missing for all races. This is true in both modules, Bugfix and New_Races. In my logs, I see many messages that look like this, one for almost every modded faction, even with the Bugfix module:
15:03:58.24 RENDER ANIM -- Art/UI/3D_Models/Salamander_Force_Commander_Frontend: Unable to open file!
When I run each faction independently, the UI works fine, so it does not seem to be a FreeUI issue but instead something specific to the Bugfix.
This appears to have been caused by the Unification Bugfix patch for Salamanders and Iron Fists.