Not a DCT owner but did have SMG in my last M3. Can't you just pull the paddles to get 3rd (in this situation) and go from there? Don't understand the need to hit the kickdown, then pull a paddle, then ... to do what you can do for yourself a la SMG?
08 E90 | Jet Black / Black | 6MT
Mods: RAC RG63 w/ Pirelli Corsa 255F/285R | Akrapovic Evo Exhaust | OEM Blacklines
Winter Setup: OEM 18s w/ Nokian Hakkapeliita R 245/40-18