OK, still not 100% sure of what we have here. It looks like for sure the installer is not able to connect to the database. Double check your settings for that. And it does complain of a wrong path. For this double check with your host. And since this is for a subdomain it will be "/your current physical path/subdomain folder" Also make sure that your host supports subdomains and define it to your folder through cPanel, or some other provided control panel.

Check my site WarPigW2.com and if available click on the "Live Help" block and we can try to sort this problem. Sorry that as yet not able to fix it for you.