Don't have time right now for a closer look but IIRC there's kind of a chicken-egg problem in this area where g_guiSettings.m_LookAndFeelResolution depends on the rendering system already being initialised to be able to choose from a list of available and valid resolutions and the fact that the rendering system needs to know about the resolution to use. It popped up once after @theuni refactored some of the "run headless" stuff.