diff --git a/src/ai/ai_gui.cpp b/src/ai/ai_gui.cpp
--- a/src/ai/ai_gui.cpp
+++ b/src/ai/ai_gui.cpp
@@ -478,21 +478,21 @@ static const NWidgetPart _nested_ai_conf
 	NWidget(WWT_PANEL, COLOUR_MAUVE, AIC_WIDGET_BACKGROUND),
 		NWidget(NWID_VERTICAL), SetPIP(4, 0, 4),
 			NWidget(NWID_HORIZONTAL), SetPIP(10, 0, 10),
-				NWidget(NWID_BUTTON_ARROW, COLOUR_YELLOW, AIC_WIDGET_DECREASE), SetFill(false, true), SetDataTip(AWV_DECREASE, STR_NULL),
-				NWidget(NWID_BUTTON_ARROW, COLOUR_YELLOW, AIC_WIDGET_INCREASE), SetFill(false, true), SetDataTip(AWV_INCREASE, STR_NULL),
+				NWidget(NWID_BUTTON_ARROW, COLOUR_YELLOW, AIC_WIDGET_DECREASE), SetFill(0, 1), SetDataTip(AWV_DECREASE, STR_NULL),
+				NWidget(NWID_BUTTON_ARROW, COLOUR_YELLOW, AIC_WIDGET_INCREASE), SetFill(0, 1), SetDataTip(AWV_INCREASE, STR_NULL),
 				NWidget(NWID_SPACER), SetMinimalSize(6, 0),
-				NWidget(WWT_TEXT, COLOUR_MAUVE, AIC_WIDGET_NUMBER), SetDataTip(STR_DIFFICULTY_LEVEL_SETTING_MAXIMUM_NO_COMPETITORS, STR_NULL), SetFill(true, false), SetPadding(1, 0, 0, 0),
+				NWidget(WWT_TEXT, COLOUR_MAUVE, AIC_WIDGET_NUMBER), SetDataTip(STR_DIFFICULTY_LEVEL_SETTING_MAXIMUM_NO_COMPETITORS, STR_NULL), SetFill(1, 0), SetPadding(1, 0, 0, 0),
 			EndContainer(),
 		EndContainer(),
 		NWidget(NWID_HORIZONTAL),
-			NWidget(WWT_MATRIX, COLOUR_MAUVE, AIC_WIDGET_LIST), SetMinimalSize(288, 112), SetFill(true, false), SetDataTip(0x801, STR_AI_CONFIG_LIST_TOOLTIP),
+			NWidget(WWT_MATRIX, COLOUR_MAUVE, AIC_WIDGET_LIST), SetMinimalSize(288, 112), SetFill(1, 0), SetDataTip(0x801, STR_AI_CONFIG_LIST_TOOLTIP),
 			NWidget(WWT_SCROLLBAR, COLOUR_MAUVE, AIC_WIDGET_SCROLLBAR),
 		EndContainer(),
 		NWidget(NWID_SPACER), SetMinimalSize(0, 9),
 		NWidget(NWID_HORIZONTAL, NC_EQUALSIZE), SetPIP(5, 0, 5),
-			NWidget(WWT_PUSHTXTBTN, COLOUR_YELLOW, AIC_WIDGET_CHANGE), SetFill(true, false), SetMinimalSize(93, 12), SetDataTip(STR_AI_CONFIG_CHANGE, STR_AI_CONFIG_CHANGE_TOOLTIP),
-			NWidget(WWT_PUSHTXTBTN, COLOUR_YELLOW, AIC_WIDGET_CONFIGURE), SetFill(true, false), SetMinimalSize(93, 12), SetDataTip(STR_AI_CONFIG_CONFIGURE, STR_AI_CONFIG_CONFIGURE_TOOLTIP),
-			NWidget(WWT_PUSHTXTBTN, COLOUR_YELLOW, AIC_WIDGET_CLOSE), SetFill(true, false), SetMinimalSize(93, 12), SetDataTip(STR_AI_SETTINGS_CLOSE, STR_NULL),
+			NWidget(WWT_PUSHTXTBTN, COLOUR_YELLOW, AIC_WIDGET_CHANGE), SetFill(1, 0), SetMinimalSize(93, 12), SetDataTip(STR_AI_CONFIG_CHANGE, STR_AI_CONFIG_CHANGE_TOOLTIP),
+			NWidget(WWT_PUSHTXTBTN, COLOUR_YELLOW, AIC_WIDGET_CONFIGURE), SetFill(1, 0), SetMinimalSize(93, 12), SetDataTip(STR_AI_CONFIG_CONFIGURE, STR_AI_CONFIG_CONFIGURE_TOOLTIP),
+			NWidget(WWT_PUSHTXTBTN, COLOUR_YELLOW, AIC_WIDGET_CLOSE), SetFill(1, 0), SetMinimalSize(93, 12), SetDataTip(STR_AI_SETTINGS_CLOSE, STR_NULL),
 		EndContainer(),
 		NWidget(NWID_SPACER), SetMinimalSize(0, 9),
 	EndContainer(),