Proxy and SBFX 4.0 problem

[hawkv]

I need help. I access the internet with a proxy, the problem that I have is that SBFX 4.0 is not working in this environment !!! When I go to the setup option and enable Proxy and click test, everything comes up normal. But when I click register account or login into an account, nothing happens. I know port 443 is open for sure, and my proxy uses port 8000 for http traffic. Do I need to worry about anything else ?

Need urgent help please...