diff --git a/src/ginput/mouse.c b/src/ginput/mouse.c
index 5459a4cd..74b5a990 100644
--- a/src/ginput/mouse.c
+++ b/src/ginput/mouse.c
@@ -514,7 +514,7 @@ bool_t ginputCalibrateMouse(uint16_t instance) {
 		#if GFX_USE_GWIN
 			gdispClear(gwinGetDefaultBgColor());
 		#else
-			gdispClear(White);
+			gdispClear(Black);
 		#endif
 	
 		return TRUE;
diff --git a/src/gwin/checkbox.c b/src/gwin/checkbox.c
index 9121a55b..7a6198de 100644
--- a/src/gwin/checkbox.c
+++ b/src/gwin/checkbox.c
@@ -190,7 +190,7 @@ void gwinCheckboxDraw_CheckOnRight(GWidgetObject *gw, void *param) {
 	if (gw->g.flags & GCHECKBOX_FLG_CHECKED)
 		gdispFillArea(gw->g.x+ep+df, gw->g.y+df, ld-2*df, ld-2*df, pcol->fill);
 
-	gdispFillStringBox(gw->g.x, gw->g.y, ep, gw->g.height, gw->text, gw->g.font, pcol->text, gw->pstyle->background, justifyRight);
+	gdispFillStringBox(gw->g.x, gw->g.y, ep-1, gw->g.height, gw->text, gw->g.font, pcol->text, gw->pstyle->background, justifyRight);
 	#undef gcw
 }
 
diff --git a/src/gwin/gwin.c b/src/gwin/gwin.c
index f5d78ac6..998fb8d3 100644
--- a/src/gwin/gwin.c
+++ b/src/gwin/gwin.c
@@ -396,7 +396,7 @@ void gwinBlitArea(GHandle gh, coord_t x, coord_t y, coord_t cx, coord_t cy, coor
 #if GDISP_NEED_PIXELREAD
 	color_t gwinGetPixelColor(GHandle gh, coord_t x, coord_t y) {
 		if (!((gh->flags & GWIN_FLG_VISIBLE)))
-			return;
+			return defaultBgColor;
 
 		#if GDISP_NEED_CLIP
 			gdispSetClip(gh->x, gh->y, gh->width, gh->height);