§1. Easy:

void RTFigures::compile_metadata(void) {
    figures_data *bf;
    LOOP_OVER(bf, figures_data) {
        inter_name *md_iname = Hierarchy::make_iname_in(INSTANCE_FIGURE_ID_MD_HL,
            RTInstances::package(bf->as_instance));
        Emit::numeric_constant(md_iname, (inter_ti) bf->figure_number);
    }
}