Hi,
the HTTPS-roundtrip error is only displayed if the connection towards the DIProxy service can't be established.
Please check that a DIProxyservice is running on server "W2K12-DEMO" (B1 server is defaulted for parameter "diproxyhost" because normally B1i and B1 are installed on the same physical machine).
If not, you can either install the DI Proxy component on your B1 server or you switch to a locally installed DIProxy service on the B1i machine (please make sure that a DI API is also installed on the B1i Server).
Best regards
Bastian