You have to drill down to the Module, or Connector, and the pin numbers are listed on the outer edges. The wiring colour codes are also shown as German two-letter abbreviations, and the wire thickness is also listed (in mm2).
For example, the high-level diagram for the convertible roof system is shown here, with the navigation menu on the left.
If you click on the green "A96" reference in the top-right of the "Convertible soft top control unit", and then navigate on the left menu to the module itself you get a diagram like the one below.
The pin numbers are arranged around the outside edge. Taking Pin 3 as an example (the top-left in the diagram above), the number, like "2.5" in this case, means it's a 2.5mm2 wire, and a colour code like "RT/GR" means it's a Red wire with a Grey stripe. It's plugged into Connector X13038, which you can click on to get more information.
A wiring connector plug/socket seems to start with an "X" as a prefix. You can navigate to even see a photo of the connector and a description of where it is. Switches have an "S" prefix, Fuses have a "F". This is what I have gathered at least in my forays into the wiring system
To get a textual list of the pin assignments you can again use the menu on the left, as shown in the clip below. The highlighted left-menu item (right at the bottom-left) brings up the list. Just have a click about and see what you can find
There's a breadcrumb trail along the top of the screen to help navigate back if necessary.
Hope that helps.
