diff --git a/src/calibre/gui2/preferences/coloring.py b/src/calibre/gui2/preferences/coloring.py
index ca30563703..d1acd0d6d8 100644
--- a/src/calibre/gui2/preferences/coloring.py
+++ b/src/calibre/gui2/preferences/coloring.py
@@ -836,6 +836,10 @@ class RulesModel(QAbstractListModel):  # {{{
                 else:
                     continue
                 break
+        if action_name == Rule.INVALID_CONDITION:
+            return (
+                _('<li>The condition using column <b>%(col)s</b> is <b>invalid</b>')
+                % dict(col=c))
         return (
             _('<li>If the <b>%(col)s</b> column <b>%(action)s</b> value: <b>%(val)s</b>') % dict(
                 col=c, action=action_name, val=prepare_string_for_xml(v)))
@@ -864,7 +868,7 @@ class EditRules(QWidget):  # {{{
         self.add_button = QPushButton(QIcon(I('plus.png')), _('Add Rule'),
                 self)
         self.remove_button = QPushButton(QIcon(I('minus.png')),
-                _('Remove Rule'), self)
+                _('Remove Rule(s)'), self)
         self.add_button.clicked.connect(self.add_rule)
         self.remove_button.clicked.connect(self.remove_rule)
         l.addWidget(self.add_button, l.rowCount(), 0)
@@ -873,7 +877,7 @@ class EditRules(QWidget):  # {{{
         self.g = g = QGridLayout()
         self.rules_view = QListView(self)
         self.rules_view.doubleClicked.connect(self.edit_rule)
-        self.rules_view.setSelectionMode(self.rules_view.SingleSelection)
+        self.rules_view.setSelectionMode(self.rules_view.ExtendedSelection)
         self.rules_view.setAlternatingRowColors(True)
         self.rtfd = RichTextDelegate(parent=self.rules_view, max_width=400)
         self.rules_view.setItemDelegate(self.rtfd)
@@ -1003,12 +1007,13 @@ class EditRules(QWidget):  # {{{
             error_dialog(self, _('No rule selected'),
                     _('No rule selected for %s.')%txt, show=True)
             return None
-        return rows[0]
+        return sorted(rows, reverse=True)
 
     def remove_rule(self):
-        row = self.get_selected_row(_('removal'))
-        if row is not None:
-            self.model.remove_rule(row)
+        rows = self.get_selected_row(_('removal'))
+        if rows is not None:
+            for row in rows:
+                self.model.remove_rule(row)
             self.changed.emit()
 
     def move_up(self):
diff --git a/src/calibre/library/coloring.py b/src/calibre/library/coloring.py
index ab8551b0d7..ef48508233 100644
--- a/src/calibre/library/coloring.py
+++ b/src/calibre/library/coloring.py
@@ -17,6 +17,8 @@ class Rule(object):  # {{{
 
     SIGNATURE = '# BasicColorRule():'
 
+    INVALID_CONDITION = _('INVALID CONDITION')
+
     def __init__(self, fm, color=None):
         self.color = color
         self.fm = fm
@@ -28,6 +30,8 @@ class Rule(object):  # {{{
         v = self.validate_condition(col, action, val)
         if v:
             raise ValueError(v)
+        if self.apply_condition((col, action, val)) is None:
+            action = self.INVALID_CONDITION
         self.conditions.append((col, action, val))
 
     def validate_condition(self, col, action, val):