!) You should find another PHP 7 compatibility checker. The 'errors' it found in bfa_m_find_in_dir.php and bfa_ata_admin.php happen to be comment lines, so the checker does not recognize comments and analyses them and throws an error if it finds something in a comment - it should ignore the entire line!
2) The warning are valid and can be dealt with by removing the file 'JSON.php' from the 'atahualpa/functions' folder and editing 'functions.php and deleting lines 96-101 which are:
HTML Code:
// Since 3.5.2: JSON for PHP 4 & 5.1:
if (!function_exists('json_decode')) {
include_once (get_template_directory() . '/functions/JSON.php');
function json_encode($data) { $json = new Services_JSON(); return( $json->encode($data) ); }
function json_decode($data) { $json = new Services_JSON(); return( $json->decode($data) ); }
}