Hello,
The error appears because in the unit sgcWebsocket_Winapi the object HINTERNET is defined, and the project makes uses of wininet (where the same object is defined too). I've modified the unit to prevent HINTERNET and INTERNET_PORT from being generated under CBuilder (if there are more objects with the same ambiguity error just let me know and I will fix it). If you've an active source code license you can download the latest from your account which includes this fix.
As a workaround, instead of make of use TsgcWebSocketClient_Winhttp, you can make use of TsgcWebSocketClient which doesn't make uses of sgcWebSocket_Winapi.
Thanks for letting me know.
Kind Regards,
Sergio