Hello,
The errors are correct for such situation. 0x00031029 means WCL_E_OBEX_OPERATION_TERMINATED_BY_USER. It may appear when server closes the connection right after send operation completed. This also indicated by the 0x00031028 error code (WCL_E_OBEX_OPERATION_TERMINATED_BY_DISCONNECT).
About the file. Once you receive OppClientPutCompleted even and accepted the file you have to save received data on your local disk if needed. The OppServer demo does not save anything that was received.
If yo utell me which edition you use (C++, .NET or VCL) I'll prepare modified demo that saves the file.