Remove the errors in your registering function:
'Gigs'
is not part of the default language file. Either add your text domain as second parameter or drop the translation function.'_builtin' => true
is wrong. Remove the parameter; it is for native post types only.'supports' => array('title', 'editor',/* 'custom-fields' */),
– the comma aftereditor
is a syntax error. Turn debugging on to see such errors.