Motorola released 7.0 kernel.
All custom roms you can flash at 6.x, I don't know which support DS.
After update to Nougat you can install LineageOS but you have to reflash modem(6.0.1 retasia ds).
---------- Post added at 02:56 PM ---------- Previous post was at 02:55 PM ----------
i flashed the 6.0.1 official (XT1572_CLARK_RETASIA_DS_6.0.1_MPHS24.107-58-5_cid7_subsidy-DEFAULT_CFC.xml.zip) from fastboot and phone booted up successfully with active dual sim (downgrade from 7.0)
i tried to install a custom rom. i flashed it from recovery. when rom booted, the phone can't recognize simacards. then i flashed the modem ASIA_DS+Marshmallow.zip from recovery but phone could not recognize simcard yet. should i extract NON-HLOS.bin from original rom and flash it from fastboot?
what should i do to enable simcards on custom rom?