Have been having a read of the VDO site and it appears that the ‘download key’ may be used to download the VU and any driver card in it at the time. To do this you will need to have the Company Card inserted in the VU at the same time. Convention says the Driver Card goes in slot 1, but for the purposes of downloading it doesn’t matter which slots the cards are inserted into. Don’t know the exact process, as I said earlier, we don’t use that particular piece of kit. From what I remember certain ‘download key’ settings are changeable by using the software that came with the kit when the key is plugged into your PC or lappy. So you don’t need to buy a separate ‘card reader’ the ‘download key’ can do both card and VU. You can get a ‘plug-in’ card reader for the ‘download key II’ which allows you to read cards straight into the ‘key’ without inserting them into a VU. TBH this looks like overkill in your case of a single motor.
Download the driver card at least every 28 days and the VU at least every 56 days. Keep the data files safe for at least 12 months, then they may be deleted. Make sure you download the VU before you sell the vehicle on, even if you haven’t got to 56 days since the last download. The downloading legislation came into force in February 2008, but don’t worry too much, just get the card downloaded now.