I had the same problem but solved it, (modifiing a bit post #452) :
1- Unpair MiBand at MiFit;
2- Install GadgetBridge and pair Miband;
3- Download and install cfw 1.5.0.2. with GadgetBridge;
4- Unpair MiBand at bluetooth settings (in cell phone);
5- Pair MiBand again with GadgetBridge;
6- Download and install V.40 resources with GadgetBridge;
(6.1- Unpair and unnistall GadgetBridge; )
7- Pair MiBand with MiFit \o/