Manual proxy error

Hi,
I'm using PortableApps.com 12.0 Beta 2. The manual proxy support would allow me to install Skype as the system proxy has the domain black listed.
Automatic proxy works fine but if I put the same setting to manual proxy I get:
"Unable to connect to PortableApps.com to retrieve portable apps. Please try again later. [ File Open Error ]"
I made small proxy program which logs requests and the platforms never connects to it.
What could be the problem? Is there some debug mode available?