1. "NVT Berendsen" is readily available in the Script Generator for MD. I'm not sure what you refer to about temperature, maybe that post was old. You can set the reservoir temperature.
2. Your question is self-contradictory, since DFTB is part of ATK-SemiEmpirical, but let me answer this way: you can perform MD simulations with any method in ATK that provides forces and energies. This includes both DFT and DFTB.