In what way has 1.5.3 added this feature, have oxwall provided a shared ssl cert?

I have been attempting to set up facebook contact importer - but still no luck after updating to 1.5.3. I have gone through all the steps provided in the oxwall documentation section.

For the secure canvas URL i have included: https://mysite.com/contactimporter/fbcanvas/

What else do i need to do from my side to get this to work?

When i click 'go to app' on facebook

google chrome says

This webpage is not availableThe webpage at https://mysite.com/contactimporter/fbcanvas/?fb_source=appcenter&fb_appcenter=1 might be temporarily down or it may have moved permanently to a new web address.Error 501 (net::ERR_INSECURE_RESPONSE): Unknown error.

FIREFOX SAYS: 

The connection is untrusted:

Technical details: uses an invalid security certificate.The certificate is only valid for the following names: *.justhost.com , justhost.com  (Error code: ssl_error_bad_cert_domain)