Heya!
Well, you must review the following posts:
Update A2Uploader V5
A2-DB3150 Flashing
Then the data pack (FS, MAIN and CDA) you'll find in Donwload Forum Area:
FS & MAIN, here:C905
and CDA, here:c905custpack
Take care: Before Flash Procedure, your phone must be charged 70% up; the FS and MAIN must belong to the same Firmware; and you must choose a CDA according to your country and phone Operator or Generic, if it isn't there.
Greetings