diff --git a/src/calibre/gui2/catalog/catalog_epub_mobi.py b/src/calibre/gui2/catalog/catalog_epub_mobi.py
index acb158a05f..9b9911b5d4 100644
--- a/src/calibre/gui2/catalog/catalog_epub_mobi.py
+++ b/src/calibre/gui2/catalog/catalog_epub_mobi.py
@@ -44,7 +44,8 @@ class PluginWidget(QWidget,Ui_Form):
         for opt in self.OPTION_FIELDS:
             opt_value = unicode(getattr(self, opt[0]).text())
             gprefs.set(self.name + '_' + opt[0], opt_value)
-            opt_value = opt_value.split(',')
+            if opt[0] != 'exclude_genre':
+                opt_value = opt_value.split(',')
             opts_dict[opt[0]] = opt_value
 
         opts_dict['output_profile'] = [load_defaults('page_setup')['output_profile']]
diff --git a/src/calibre/gui2/convert/gui_conversion.py b/src/calibre/gui2/convert/gui_conversion.py
index 7941586274..67c50758f8 100644
--- a/src/calibre/gui2/convert/gui_conversion.py
+++ b/src/calibre/gui2/convert/gui_conversion.py
@@ -49,7 +49,10 @@ def gui_catalog(fmt, title, dbspec, ids, out_file_name, fmt_options,
 
     # Extract the option dictionary to comma-separated lists
     for option in fmt_options:
-        setattr(opts,option, ','.join(fmt_options[option]))
+        if isinstance(fmt_options[option],list):
+            setattr(opts,option, ','.join(fmt_options[option]))
+        else:
+            setattr(opts,option, fmt_options[option])
 
     # Fetch and run the plugin for fmt
     plugin = plugin_for_catalog_format(fmt)
diff --git a/src/calibre/gui2/dialogs/catalog.py b/src/calibre/gui2/dialogs/catalog.py
index 56f2bd1f6f..7009824679 100644
--- a/src/calibre/gui2/dialogs/catalog.py
+++ b/src/calibre/gui2/dialogs/catalog.py
@@ -36,9 +36,6 @@ class Catalog(QDialog, Ui_Dialog):
         self.title.setText(dynamic.get('catalog_last_used_title',
             _('My Books')))
 
-        # GwR *** Add option tabs for built-in formats
-        # This code models #69 in calibre/gui2/dialogs/config/__init__.py
-
         self.fmts, self.widgets = [], []
 
         from calibre.customize.builtins import plugins as builtin_plugins
diff --git a/src/calibre/library/catalog.py b/src/calibre/library/catalog.py
index 56d06572cf..b62d1a0f29 100644
--- a/src/calibre/library/catalog.py
+++ b/src/calibre/library/catalog.py
@@ -2484,16 +2484,10 @@ class EPUB_MOBI(CatalogPlugin):
             for tag in tags:
                 tag = self.convertHTMLEntities(tag)
                 if tag.startswith(opts.note_tag):
-    #                 if opts.verbose:
-    #                     print "%s has a note: %s" % (this_title['title'], tag[1:])
                     this_title['notes'] = tag[1:]
                 elif tag == opts.read_tag:
-    #                 if opts.verbose:
-    #                     print "%s marked as read" % this_title['title']
                     this_title['read'] = True
                 elif re.search(opts.exclude_genre, tag):
-    #                 if opts.verbose:
-    #                     print "'%s' matches exclude_genre regex, skipping" % tag
                     continue
                 else:
                     tag_list.append(tag)