Make sure that the permissions on the webassist folder and all files and folders under it are set to 755. I recommend using a dedicated FTP program like filezilla to change file permissions.
Then, in the webassist/caching/PG_CachedResize_Image.php file needs to be updated to
change line 14:
$retVal = is_dir($pathname) || @mkdir($pathname, 0777);
to:
$retVal = is_dir($pathname) || @mkdir($pathname, 0755);
and line 360:
[php]mkdir ($cachefolder,0777,true);[php]
to:
[php]mkdir ($cachefolder,0755,true);/php]
And the admin_gallery/common/properties.php file needs to be edited to
change:
$GLOBALS['permissions'] = array(
'dir' => 0777,
'file' => 0666
);
To:
$GLOBALS['permissions'] = array(
'dir' => 0755,
'file' => 0755
);