I just changed the tongue damper on a 10/2007 Cobra.
Had been in procrastination mode. Perhaps others put that job off too?
Thanks for keeping the thread going as a reminder!
It took 90 minutes from chocking and jacking the trailer prior to removal until rolling it out with the new part installed.
This part I believe is critical in maintaining good braking behaviour.

There is an Al-Ko Workshop manual, covering axles, brakes, hitches and overrun devices. It also has lists of lubricants and accessories.

http://www.tabberiet.dk/T%40B-siden/...al%20AL-KO.pdf

The missing information for those with the square tongue:

Remove the jockey wheel.
After disconnecting the brake rod, remove the two bolts holding the drawbar onto the tongue.
Remove the drawbar.

Tools:
17mm open end for the brake rod. 19mm socket and open or box for the other bolts. Alignment tool for the new damper. Torque wrench.
Options:
Hammer, beer.
Jim