diff --git a/debug.scad b/debug.scad
index c2568c9b..a38a6900 100644
--- a/debug.scad
+++ b/debug.scad
@@ -301,6 +301,22 @@ module anchor_arrow(s=10, color=[0.333,0.333,1], flag=true, $tags="anchor-arrow"
 
 
 
+// Module: anchor_arrow2d()
+// Usage:
+//   anchor_arrow2d([s], [color], [flag]);
+// Description:
+//   Show an anchor orientation arrow.
+// Arguments:
+//   s = Length of the arrows.
+//   color = Color of the arrow.
+// Example:
+//   anchor_arrow2d(s=20);
+module anchor_arrow2d(s=15, color=[0.333,0.333,1], $tags="anchor-arrow") {
+    noop() stroke([[0,0],[0,s]], width=s/10, endcap1="butt", endcap2="arrow2");
+}
+
+
+
 // Module: show_internal_anchors()
 // Usage:
 //   show_internal_anchors() ...
diff --git a/mutators.scad b/mutators.scad
index f704bdc8..80b9752a 100644
--- a/mutators.scad
+++ b/mutators.scad
@@ -27,15 +27,15 @@
 //   translate([10,8,4]) cube(5);
 //   translate([3,0,12]) cube(2);
 module bounding_box(excess=0) {
-    xs = excess>0? excess : 1;
+    xs = excess>.1? excess : 1;
     // a 3D approx. of the children projection on X axis
     module _xProjection()
         linear_extrude(xs, center=true)
-            hull()
-                projection()
-                    rotate([90,0,0])
-                        linear_extrude(xs, center=true)
-                            projection()
+            projection()
+                rotate([90,0,0])
+                    linear_extrude(xs, center=true)
+                        projection()
+                            hull()
                                 children();
 
     // a bounding box with an offset of 1 in all axis
@@ -50,13 +50,13 @@ module bounding_box(excess=0) {
     // offset children() (a cube) by -1 in all axis
     module _shrink_cube() {
         intersection() {
-            translate([ 1, 1, 1]) children();
-            translate([-1,-1,-1]) children();
+            translate((1-excess)*[ 1, 1, 1]) children();
+            translate((1-excess)*[-1,-1,-1]) children();
         }
     }
 
     render(convexity=2)
-    if (excess>0) {
+    if (excess>.1) {
         _oversize_bbox() children();
     } else {
         _shrink_cube() _oversize_bbox() children();
@@ -674,7 +674,7 @@ module minkowski_difference() {
                     bounding_box(excess=1) children(0);
                     children(0);
                 }
-                for (i=[1,1,$children-1]) children(i);
+                for (i=[1:1:$children-1]) children(i);
             }
         }
     }
diff --git a/version.scad b/version.scad
index 76088b4e..e533b27d 100644
--- a/version.scad
+++ b/version.scad
@@ -8,7 +8,7 @@
 //////////////////////////////////////////////////////////////////////
 
 
-BOSL_VERSION = [2,0,480];
+BOSL_VERSION = [2,0,482];
 
 
 // Section: BOSL Library Version Functions