Very common problem for our cars. One simple solution is to run your car with the gear shift in "Sport" mode. This forces the transmission to downshift a little earlier (higher RPM) when coming to a stop avoiding that jerkiness when downshifting to 1st. Another option is to have the dealer raise the idle speed about 100 rpm. Many forum members have had success with that method also.
The underlining problem is that the transmission control valve assemble contains a lot of small o-rings, solenoid valves and hydraulic ports that accumulate wear deposits (In spite of the filter) that hinder the smooth operation when like new. This coupled with the relatively low idle RPM causes the abrupt shifting when coming to a stop. Nothing short of rebuilding the valve assembly will totally cure the situation.
BTW, in Europe, ZF Transmissions offers this rebuild service for about $500 as they consider it part of the required maintenance. They recommend that it be done every 60-70,000 miles. By all accounts it is well worth it.
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