I'm not completely sure, but it probably has something to do with the way you're calling your functions and the way you're assigning values to the variables. The way I troubleshoot something like this is to echo variables at various places in your code, and make small changes at a time. PHP errors tend to not be very informative.
Your domain record was missing from ns1.heliohost.org so when your browser randomly selected that nameserver to find the IP of your domain your website would show up as offline. When your browser select ns2.heliohost.org your website would show up as online. I have synced up the records so it shouldn't be a problem anymore. Thanks for pointing this out.
Here is the error:
(XID vbmxbp) The system cannot accept “nst” as a domain name (domain name must have a valid TLD label).
I'm assuming you meant to make it http://nst.heliohost.org/ ? I have requeued your account for you.
Yep. Johnny has 5.6. If you want more control and don't mind donating for an invite, Tommy has 5.4 through 7.0 (you can pick for each domain or subdomain in your account).