Worst cast scenario you just need to modify the cable & stuck a switch on it to toggle pin 8 on/off as needed. The ones with pin 8 active are just older versions of the cable. The one with it disabled is ideal for e90 newer than 03/07 & that era, these leads often come with a black adapter to re-enable the pin 8 (by just tying it to pin 9) so it will also be suitable for e46/e39/e63 etc. Also with these cables there are two subtle different versions, one with pin 8 enabled, one with it disabled. I'll try update over the weekend with instructions, pictures, etc. It is a bit confusing trying to get it all to work. However a lot of sellers don't mention or probably don't even know what these are. Once you have them they are great though. With the USB K+ D CAN type cables there are a few installation steps, drivers & a little app that you need to make them work properly. The VAG-COM one you'll need to do some slight modifications for coding & programming but will work for fault code reading unmodified. USB to serial or PCMCIA will not work for some modules on older cars (fine for newer stuff) a lead with the serial port type connector For older cars with the big round diagnostic connector under the bonnet you'll need:

It works on all current models as well as everything for e46/e39 era. K+D CAN with USB (opaque colour casing)

Inpa bmw e38