- add_pv('start', current_data['position']['history'], 1, 'W', null, 0, 8, true);
+ var start = (current_data['position'] && current_data['position']['start_fen']) ? current_data['position']['start_fen'] : 'start';
+ add_pv(start, current_data['position']['history'], 1, 'W', null, 0, 8, true);