diff --git a/constants.py b/constants.py
index 6efe1a1d..496fcbc1 100644
--- a/constants.py
+++ b/constants.py
@@ -79,6 +79,12 @@ TEX_IMAGE_DIR     = TEX_DIR #TODO, What is this doing?
 MOBJECT_DIR       = os.path.join(FILE_DIR, "mobjects")
 IMAGE_MOBJECT_DIR = os.path.join(MOBJECT_DIR, "image")
 
+if not os.path.exists(MEDIA_DIR):
+    raise Exception("""
+        Redefine MEDIA_DIR in constants.py to point to 
+        a valid directory where movies and images will 
+        be written
+    """)
 for folder in [FILE_DIR, RASTER_IMAGE_DIR, SVG_IMAGE_DIR, ANIMATIONS_DIR, TEX_DIR,
                TEX_IMAGE_DIR, MOBJECT_DIR, IMAGE_MOBJECT_DIR,
                STAGED_SCENES_DIR]:
diff --git a/mobject/tex_mobject.py b/mobject/tex_mobject.py
index fe5a3cdd..8401f5b7 100644
--- a/mobject/tex_mobject.py
+++ b/mobject/tex_mobject.py
@@ -87,7 +87,7 @@ class TexMobject(SVGMobject):
             should_replace = reduce(op.and_, [
                 t1 in tex,
                 t2 not in tex,
-                len(tex) > len(t1) and tex[len(t1)] in "()[]|\\"
+                len(tex) > len(t1) and tex[len(t1)] in "()[]<>|.\\"
             ])
             if should_replace:
                 tex = tex.replace(t1, "\\big")
@@ -166,9 +166,16 @@ class TexMobject(SVGMobject):
             part.highlight(color)
         return self
 
-    def highlight_by_tex_to_color_map(self, tex_to_color_map):
-        for tex, color in tex_to_color_map.items():
-            self.highlight_by_tex(tex, color)
+    def highlight_by_tex_to_color_map(self, texs_to_color_map, **kwargs):
+        for texs, color in texs_to_color_map.items():
+            try:
+                # If the given key behaves like strings
+                texs + ''
+                self.highlight_by_tex(texs, color, **kwargs)
+            except TypeError:
+                # If the given key is a tuple
+                for tex in texs:
+                    self.highlight_by_tex(tex, color, **kwargs)
         return self
 
     def index_of_part(self, part):
diff --git a/topics/objects.py b/topics/objects.py
index c8c4d13a..7fc5d69b 100644
--- a/topics/objects.py
+++ b/topics/objects.py
@@ -493,6 +493,8 @@ class Broadcast(LaggedStart):
         "small_radius" : 0.0,
         "big_radius" : 5,
         "n_circles" : 5,
+        "start_stroke_width" : 8,
+        "color" : WHITE,
         "remover" : True,
         "lag_ratio" : 0.7,
         "run_time" : 3,
@@ -510,7 +512,7 @@ class Broadcast(LaggedStart):
             circle.move_to(focal_point)
             circle.save_state()
             circle.scale_to_fit_width(self.small_radius*2)
-            circle.set_stroke(WHITE, 8)
+            circle.set_stroke(self.color, self.start_stroke_width)
             circles.add(circle)
         LaggedStart.__init__(
             self, ApplyMethod, circles,