Thats quite the unique name you have there, but anyway i recently had to do some work on my sunroof. I have an 86 Euro 190E2.3 16V and there should be a small gold clip that the cable connects to on the sunroof and you should be able to see the cable running all the way back to the back of the roof. I would check to make sure there is nothing in the way of the cable inside the roof. Also you can actually pull out the entire cable easily and re install it very easily. the cable may be shot and have a break in it somewhere, so if i was you i would run the motor out until it cannot eject the cable any further and then just pull out the cable. That way you should be able to inspect the cable for any problems. If the cable is fine you probably need to replace that little gold clip. It can become bent over time and cause the sunroof to not function properly. If neither of the two work out to be the problem i really dont know what else it could be other than a problem with the motor, which you can access in the trunk, by removing the plastic gaurd on the left hand side.
Good luck, Pete
Any questions fill me in.
1986 Euro Black Metallic 190E 2.3 16V