diff --git a/lib/elements/element.py b/lib/elements/element.py
index 10b1852ad..e85657cd1 100644
--- a/lib/elements/element.py
+++ b/lib/elements/element.py
@@ -283,5 +283,6 @@ class EmbroideryElement(object):
 
         # L10N used when showing an error message to the user such as
         # "Some Path (path1234): error: satin column: One or more of the rungs doesn't intersect both rails."
-        print >> sys.stderr, "%s: %s %s" % (name, _("error:"), message.encode("UTF-8"))
+        error_msg = "%s: %s %s" % (name, _("error:"), message)
+        print >> sys.stderr, "%s" % (error_msg.encode("UTF-8"))
         sys.exit(1)
diff --git a/lib/elements/fill.py b/lib/elements/fill.py
index 357adf4b7..7ccf7b27e 100644
--- a/lib/elements/fill.py
+++ b/lib/elements/fill.py
@@ -1,6 +1,7 @@
 import math
 
 from shapely import geometry as shgeo
+from shapely.validation import explain_validity
 
 from ..i18n import _
 from ..stitches import legacy_fill
@@ -104,37 +105,23 @@ class Fill(EmbroideryElement):
     @property
     @cache
     def shape(self):
-        poly_ary = []
-        for sub_path in self.paths:
-            point_ary = []
-            last_pt = None
-            for pt in sub_path:
-                if (last_pt is not None):
-                    vp = (pt[0] - last_pt[0], pt[1] - last_pt[1])
-                    dp = math.sqrt(math.pow(vp[0], 2.0) + math.pow(vp[1], 2.0))
-                    # dbg.write("dp %s\n" % dp)
-                    if (dp > 0.01):
-                        # I think too-close points confuse shapely.
-                        point_ary.append(pt)
-                        last_pt = pt
-                else:
-                    last_pt = pt
-            if len(point_ary) > 2:
-                poly_ary.append(point_ary)
-
-        if not poly_ary:
-            self.fatal(_("shape %s is so small that it cannot be filled with stitches.  Please make it bigger or delete it.") % self.node.get('id'))
-
         # shapely's idea of "holes" are to subtract everything in the second set
         # from the first. So let's at least make sure the "first" thing is the
         # biggest path.
-        # TODO: actually figure out which things are holes and which are shells
-        poly_ary.sort(key=lambda point_list: shgeo.Polygon(point_list).area, reverse=True)
-
-        polygon = shgeo.MultiPolygon([(poly_ary[0], poly_ary[1:])])
+        paths = self.paths
+        paths.sort(key=lambda point_list: shgeo.Polygon(point_list).area, reverse=True)
+        polygon = shgeo.MultiPolygon([(paths[0], paths[1:])])
 
         if not polygon.is_valid:
-            self.fatal(_("shape is not valid.  This can happen if the border crosses over itself."))
+            why = explain_validity(polygon)
+
+            # I Wish this weren't so brittle...
+            if "Hole lies outside shell" in why:
+                self.fatal(_("this object is made up of unconnected shapes.  This is not allowed because "
+                             "Ink/Stitch doesn't know what order to stitch them in.  Please break this "
+                             "object up into separate shapes."))
+            else:
+                self.fatal(_("shape is not valid.  This can happen if the border crosses over itself."))
 
         return polygon
 
diff --git a/lib/elements/satin_column.py b/lib/elements/satin_column.py
index bfa393847..d3c4d3d3a 100644
--- a/lib/elements/satin_column.py
+++ b/lib/elements/satin_column.py
@@ -325,6 +325,10 @@ class SatinColumn(EmbroideryElement):
             self.fatal(_("satin column: object %s has a fill (but should not)") % node_id)
 
         if not self.rungs:
+            if len(self.rails) < 2:
+                self.fatal(_("satin column: object %(id)s has too few paths.  A satin column should have at least two paths (the rails).") %
+                           dict(id=node_id))
+
             if len(self.rails[0]) != len(self.rails[1]):
                 self.fatal(_("satin column: object %(id)s has two paths with an unequal number of points (%(length1)d and %(length2)d)") %
                            dict(id=node_id, length1=len(self.rails[0]), length2=len(self.rails[1])))
diff --git a/lib/elements/utils.py b/lib/elements/utils.py
index 87dfa877b..5c71de2e7 100644
--- a/lib/elements/utils.py
+++ b/lib/elements/utils.py
@@ -16,7 +16,7 @@ def node_to_elements(node):
     elif node.tag == SVG_PATH_TAG:
         element = EmbroideryElement(node)
 
-        if element.get_boolean_param("satin_column"):
+        if element.get_boolean_param("satin_column") and element.get_style("stroke"):
             return [SatinColumn(node)]
         else:
             elements = []
diff --git a/lib/extensions/embroider.py b/lib/extensions/embroider.py
index 1a5780315..b90896120 100644
--- a/lib/extensions/embroider.py
+++ b/lib/extensions/embroider.py
@@ -39,10 +39,14 @@ class Embroider(InkstitchExtension):
 
     def get_output_path(self):
         if self.options.output_file:
-            output_path = os.path.join(os.path.expanduser(os.path.expandvars(self.options.path)), self.options.output_file)
+            # This is helpful for folks that run the embroider extension
+            # manually from the command line (without Inkscape) for
+            # debugging purposes.
+            output_path = os.path.join(os.path.expanduser(os.path.expandvars(self.options.path.decode("UTF-8"))),
+                                       self.options.output_file.decode("UTF-8"))
         else:
             csv_filename = '%s.%s' % (self.get_base_file_name(), self.options.output_format)
-            output_path = os.path.join(self.options.path, csv_filename)
+            output_path = os.path.join(self.options.path.decode("UTF-8"), csv_filename)
 
         def add_suffix(path, suffix):
             if suffix > 0:
diff --git a/lib/extensions/params.py b/lib/extensions/params.py
index 4d04ba230..a3ba77848 100644
--- a/lib/extensions/params.py
+++ b/lib/extensions/params.py
@@ -138,8 +138,11 @@ class ParamsTab(ScrolledPanel):
 
         if self.toggle:
             checked = self.enabled()
-            if self.toggle_checkbox in self.changed_inputs and not self.toggle.inverse:
-                values[self.toggle.name] = checked
+            if self.toggle_checkbox in self.changed_inputs:
+                if self.toggle.inverse:
+                    values[self.toggle.name] = not checked
+                else:
+                    values[self.toggle.name] = checked
 
             if not checked:
                 # Ignore params on this tab if the toggle is unchecked,
diff --git a/lib/stitches/auto_fill.py b/lib/stitches/auto_fill.py
index 9d946ae2e..8c8cdefd1 100644
--- a/lib/stitches/auto_fill.py
+++ b/lib/stitches/auto_fill.py
@@ -312,6 +312,15 @@ def travel_grating(shape, angle, row_spacing):
     return shgeo.MultiLineString(segments)
 
 
+def ensure_multi_line_string(thing):
+    """Given either a MultiLineString or a single LineString, return a MultiLineString"""
+
+    if isinstance(thing, shgeo.LineString):
+        return shgeo.MultiLineString([thing])
+    else:
+        return thing
+
+
 def build_travel_edges(shape, fill_angle):
     r"""Given a graph, compute the interior travel edges.
 
@@ -359,10 +368,10 @@ def build_travel_edges(shape, fill_angle):
                  for ls in mls
                  for coord in ls.coords]
 
-    diagonal_edges = grating1.symmetric_difference(grating2)
+    diagonal_edges = ensure_multi_line_string(grating1.symmetric_difference(grating2))
 
     # without this, floating point inaccuracies prevent the intersection points from lining up perfectly.
-    vertical_edges = snap(grating3.difference(grating1), diagonal_edges, 0.005)
+    vertical_edges = ensure_multi_line_string(snap(grating3.difference(grating1), diagonal_edges, 0.005))
 
     return endpoints, chain(diagonal_edges, vertical_edges)
 
diff --git a/lib/svg/units.py b/lib/svg/units.py
index 0de410ab9..739dcbb49 100644
--- a/lib/svg/units.py
+++ b/lib/svg/units.py
@@ -1,7 +1,8 @@
 import simpletransform
 
-from ..utils import cache
 from ..i18n import _
+from ..utils import cache
+
 
 # modern versions of Inkscape use 96 pixels per inch as per the CSS standard
 PIXELS_PER_MM = 96 / 25.4
@@ -91,6 +92,15 @@ def get_doc_size(svg):
     width = svg.get('width')
     height = svg.get('height')
 
+    if width == "100%" and height == "100%":
+        # Some SVG editors set width and height to "100%".  I can't find any
+        # solid documentation on how one is supposed to interpret that, so
+        # just ignore it and use the viewBox.  That seems to have the intended
+        # result anyway.
+
+        width = None
+        height = None
+
     if width is None or height is None:
         # fall back to the dimensions from the viewBox
         viewbox = get_viewbox(svg)