I am getting a similar error and seeing this under my response tab:
Notice: Undefined index: selector in /var/www/evan/plugins/Neatline/helpers/Styles.php on line 42
Notice: Undefined index: selector in /var/www/evan/plugins/Neatline/helpers/Styles.php on line 42
Notice: Undefined index: selector in /var/www/evan/plugins/Neatline/helpers/Styles.php on line 42
{"owner_id":10,"item_id":null,"exhibit_id":22,"added":null,"modified":"2014-07-24 12:04:06","is_coverage":0,"is_wms":0,"slug":null,"title":null,"item_title":null,"body":null,"coverage":null,"tags":null,"widgets":null,"presenter":"StaticBubble","fill_color":"#00aeff","fill_color_select":"#00aeff","stroke_color":"#000000","stroke_color_select":"#000000","fill_opacity":0.3,"fill_opacity_select":0.4,"stroke_opacity":0.9,"stroke_opacity_select":1,"stroke_width":2,"point_radius":10,"zindex":null,"weight":null,"start_date":null,"end_date":null,"after_date":null,"before_date":null,"point_image":null,"wms_address":null,"wms_layers":null,"min_zoom":null,"max_zoom":null,"map_zoom":null,"map_focus":null,"id":"542"}
Does that mean anything to you?