Error: AWStats database directory defined in config file by 'DirData' parameter (/home/admin/domains/download.asusforum.net/awstats/.data) does not exist or is not writable.

Setup ('/home/c100000/domains/download.asusforum.net/awstats/.data/awstats.download.asusforum.net.conf' file, web server or permissions) may be wrong.
Check config file, permissions and AWStats documentation (in 'docs' directory).