Passed variable is not an array or object / argument should be an array

What is you PHP version?

>The problem came out only when I try to create some new content.

What content are you creating? Does it have multicolumn checkboxes/radios in it?

Can you insert some debug print out?

  for ($i = 0 ; $i < $width ; ++$i) {                              //  <=========  line   321
    $height = ceil(($total - $counter) / ($width - $i));
    $a[$i] = array_slice($keys, $counter, $height);
    $counter += $height;
  }

error_log('=========$items===============');
error_log(print_r($items, TRUE));
error_log('=========$keys===============');
error_log(print_r($keys, TRUE));
error_log('=========$a===============');
error_log(print_r($a, TRUE));


  // transpose
  array_unshift($a, NULL);
  $b = call_user_func_array('array_map', $a);
  // transpose can result in NULL value at the end, clear them
  $last_row = &$b[count($b) - 1];                              //   <============     line 331

error_log('=========$b===============');
error_log(print_r($b, TRUE));
error_log('=========$last_row===============');
error_log(print_r($last_row, TRUE));


  while (end($last_row) == NULL) {               // <==========   line 332
    array_pop($last_row);                           // <==========    line 333
  }

Copy the output from php log and paste here.

Thank you for the feedback. I know what the problem is and it should be fixed in version 1.6 I just released. Please give it a try. The radios 'Bozza' and 'Lavoro finito' should just display in one column.