Not sure of this could apply, but the "Sport" in the DCS seems to have been a spinoff of a feature they put on the "S" or SE models as a means to Hold a gear during hills, downshifting and even accelleration - prevents the system from using Overdrive and it's "lockup" when the speeds are too low to make the lockup efficient. Which is their judgement - not mine.
Looks for this
The Car on a Hill light on the Dash lites up when that switch on the shifter is pressed.
That "holds" gears for both acceleration and deceleration.
Although mostly used for people on icy or slippery roads, does come in handy on wet pavement too in helping to slow down the car by keeping it in a gear versus the more "freewheeling" effect you get when you back off the throttle let the vehicle coast.
Give it a try - see if it does what you want the car to do.
Else the "S" and the transmission supplied with them, is somewhat limited in capability.