Here's another test: Could you show me how the attached demo behaves in MacOS? It shows two more LCL controls, a TStringGrid with checkbox column, and a TCheckCombobox. In both controls, the checkboxes are drawn using the theme services, like in TChartlistbox. If checks are not displayed here again then this is an argument that theme services for checkboxes are not correctly implemented for MacOS. (TCheckListBox that you already tested passes the drawing task to the widget set).