I have read this a few times too and am still having trouble understanding the problem, but it sounds like it could be the B2 band piston.
If...
It shifts into Reverse easily. In the first two gears it is very hard to get it to shift, it flares and usually takes some tries of revving and letting of on the accelerator to make it shift. But once you get to 3rd gear you are fine. You can drive on the highway with no problem, sometimes even accelerating to pass someone downshifting to 3rd and then back up to 4th without a problem. But if you come to a stop it starts having problems again, maybe even some slight jerking as it downshifts through 1st and 2nd as you come to a stop.
If this is familiar, then I think you have a busted B2 Band Piston. Do a search on the forum and read some of the posts about how others have done this. Basically, Mercedes used a metal ring for the B2 Band which eventually wears out and destroys the Piston the new part is plastic. One of the only times a plastic part is an upgrade from the originally designed metal part.
Also
check out Diesel Giant's pictorial which is helpful along with the input you will get on this site.