You can extract data using SQL connector - which requires to import the QV connector transports into BW + installation of the connector on your QV developer workstation
Or, you can extract data using OLAP connector - which requires only the installation of the connector on the QV developer workstation (without any transports)
I suggest you download the connector manual. You will find detailed prerequisites in it.
You have the right tool. SAP Connector will get you a variety of powerful connection options.
If you are primarily wanting to connect to BW you can use:
SAP SQL Connector
SAP DSO Connector
SAP Extractor Connector
SAP OLAP Connector
Depending on what you trying to do, you will chose one of them The documentation is really good for this product. Please look at the QlikView Connector Manual.pdf http://us.demo.qlik.com/download/
refer to the trread QlikView SAP Connector to SAP BW