I just checked your url, and everything looks good. Your problem(s) might have bben related to DNS propagation, as you indicated you used a subdomain.
It has been my experience that, while “one-click” works very well, the DH screens and email notifications are often very optimistic about when things will be “ready”. Even if the database is made, the virtual host is created, and everything else on the DH side is done, there can still be delays while the DNS propagates (for both the domain and the MySQL host). I’ve seen users get the email that “all is ready”, then go to the site to complete the install steps and have it break because the MySQL host cannot be reached, etc.
Sometime, patience id a virtue; you don’t things “fixed” andy quicker, but it is a lot less stressfull.