Solved to:
$array1 = $aDefaultOptions;
$array2 = $aSetOptions;
$aOptions = array_merge($array1, (array) $array2);
I have a question, I still get this error –
PS Auto Sitemap isn't using cache system currently, because cache or parent directorty isn't writable. Please check owner and permission of upload directory.
where the hell is tha cache directory supposed to be ?