Very little actually works, but a working base to start from.
Left is the sad original case of unreadable menubar and missing sidebar icons. Right is the newly fixed case with legible menubar and restored sidebar icons. Additionally the "default" buttons of dialogs ("insert" in this case) are now using the correct text color, preview is visible, and EditBoxes render with the correct border color for focus and mouse over. Normal themes also gain a more subtle border color in Edits to indicate focus.
Writer supports Small Caps, but Impress and drawing shapes in general never fully supported Small Caps. The option was available, and the character dialog provided a preview, but Small Caps was rendered the same as All Caps, as seen here.