1) How can I see what firmware version I have? I have an SLK (171) with Comand APS NTG 2.5 with HDD/Navigator/6DVD etc. Hello, I have an SLK (171) with Comand APS NTG 2.5 with HDD/Navigator/6DVD etc. You can call us with any questions if you are unsure. The disc will then eject, it does not need to stay in the unit. A pop-up window on the unit's screen will show confirming the upgrade, it can take 30-40 minutes on average. Simply check your vehicle uses the same disc type, purchase the DVD, switch on the unit in the dash, eject all your current discs in the unit, insert the new navigation disc and wait. If you need to update your Mercedes Benz navigation unit with the latest Australian or New Zealand maps then it's a very simple process. Navigation DVD for Mercedes-Benz Comand APS Radio Systems NTG 2.5 - Latest Genuine Version! El Opio De Los Intelectuales Pdf.