Note that SAP doesn’t provide demo version of BI tool. Only trial available is for SAP Basis and Java Stack and these doesn’t include any ERP modules. Without availability of any ERP module, it hardly makes sense to use SAP BW demo version as there won’t be any sensible scenario to be used in BI.
I would suggest you to use IDES which comes with fully configured business scenarios and BW functionality for demo.
To know more about SAP BI 7.0 IDES system, you can refer this SAP thread −