diff --git a/src/calibre/gui2/catalog/catalog_epub_mobi.py b/src/calibre/gui2/catalog/catalog_epub_mobi.py
index ac51dd08bb..1ed11a55d7 100644
--- a/src/calibre/gui2/catalog/catalog_epub_mobi.py
+++ b/src/calibre/gui2/catalog/catalog_epub_mobi.py
@@ -75,7 +75,7 @@ class PluginWidget(QWidget,Ui_Form):
                             ['radio_button' for i in RadioButtonControls])
 
         # LineEditControls
-        option_fields += zip(['exclude_genre'],['\[.+\]|\+'],['line_edit'])
+        option_fields += zip(['exclude_genre'],['\[.+\]|^\+$'],['line_edit'])
 
         # TextEditControls
         #option_fields += zip(['exclude_genre_results'],['excluded genres will appear here'],['text_edit'])
@@ -156,6 +156,32 @@ class PluginWidget(QWidget,Ui_Form):
         Output:
          self.exclude_genre_results (QLabel): updated to show tags to be excluded as genres
         """
+        def _truncated_results(excluded_tags, limit=180):
+            '''
+            Limit number of genres displayed to avoid dialog explosion
+            '''
+            start = []
+            end = []
+            lower = 0
+            upper = len(excluded_tags) -1
+            excluded_tags.sort()
+            while True:
+                if lower > upper:
+                    break
+                elif lower == upper:
+                    start.append(excluded_tags[lower])
+                    break
+                start.append(excluded_tags[lower])
+                end.insert(0,excluded_tags[upper])
+                if len(', '.join(start)) + len(', '.join(end)) > limit:
+                    break
+                lower += 1
+                upper -= 1
+            if excluded_tags == start + end:
+                return ', '.join(excluded_tags)
+            else:
+                return "%s  ...  %s" % (', '.join(start), ', '.join(end))
+
         results = _('No genres will be excluded')
         if not regex:
             self.exclude_genre_results.clear()
@@ -176,7 +202,7 @@ class PluginWidget(QWidget,Ui_Form):
                 if set(excluded_tags) == set(self.all_tags):
                     results = _("All genres will be excluded")
                 else:
-                    results = ', '.join(sorted(excluded_tags))
+                    results = _truncated_results(excluded_tags)
         finally:
             if self.DEBUG:
                 print(results)
diff --git a/src/calibre/gui2/catalog/catalog_epub_mobi.ui b/src/calibre/gui2/catalog/catalog_epub_mobi.ui
index 5e3a195190..b32e596f54 100644
--- a/src/calibre/gui2/catalog/catalog_epub_mobi.ui
+++ b/src/calibre/gui2/catalog/catalog_epub_mobi.ui
@@ -208,7 +208,7 @@ The default pattern \[.+\]|\+ excludes tags of the form [tag], e.g., [Test book]
          </size>
         </property>
         <property name="toolTip">
-         <string extracomment="Default: \[[\w]*\]"/>
+         <string/>
         </property>
        </widget>
       </item>
@@ -223,7 +223,7 @@ The default pattern \[.+\]|\+ excludes tags of the form [tag], e.g., [Test book]
        </widget>
       </item>
       <item row="1" column="0">
-       <widget class="QLabel" name="label_2">
+       <widget class="QLabel" name="regex_results_label">
         <property name="minimumSize">
          <size>
           <width>175</width>
diff --git a/src/calibre/library/catalogs/epub_mobi.py b/src/calibre/library/catalogs/epub_mobi.py
index 9db05d5076..6225612cc8 100644
--- a/src/calibre/library/catalogs/epub_mobi.py
+++ b/src/calibre/library/catalogs/epub_mobi.py
@@ -51,7 +51,7 @@ class EPUB_MOBI(CatalogPlugin):
                            "Default: '%default'\n"
                            "Applies to: AZW3, ePub, MOBI output formats")),
                    Option('--exclude-genre',
-                          default='\[.+\]|\+',
+                          default='\[.+\]|^\+$',
                           dest='exclude_genre',
                           action = None,
                           help=_("Regex describing tags to exclude as genres.\n"
@@ -313,18 +313,16 @@ class EPUB_MOBI(CatalogPlugin):
         keys.sort()
         build_log.append(" opts:")
         for key in keys:
-            if key in ['catalog_title','author_clip','connected_kindle','description_clip',
-                       'exclude_book_marker','exclude_genre','exclude_tags',
-                       'exclusion_rules', 'fmt',
+            if key in ['catalog_title','author_clip','connected_kindle','creator',
+                       'description_clip','exclude_book_marker','exclude_genre',
+                       'exclude_tags','exclusion_rules', 'fmt',
                        'header_note_source_field','merge_comments_rule',
                        'output_profile','prefix_rules','read_book_marker',
                        'search_text','sort_by','sort_descriptions_by_author','sync',
                        'thumb_width','use_existing_cover','wishlist_tag']:
                 build_log.append("  %s: %s" % (key, repr(opts_dict[key])))
-
         if opts.verbose:
             log('\n'.join(line for line in build_log))
-
         self.opts = opts
 
         # Launch the Catalog builder