Firmware Update Steps:
Run Samsung S3650 Downloader and select BRCM2133.
If you want to flash Boot files then check: Full Download
For Boot select the Boot files Folder from the Firmware folder which you want to use.
For Apps select: apps_compressed.bin
For Rsrc1 select: Rsrc_S3650_Open_Europe_Common.rc1
For Rsrc2 select: Rsrc2_S3650(Low).rc2
For Factory FS select: FactoryFs_S3650_Open_Europe_Common.ffs
Put the phone into download mode: Press Volume down + Camera + Power.
Connect the phone to PC by USB cable and click Port Search to make sure of good connection.
Click Download to start the process and wait till the phone rebooted.
Do full reset : *2767*3855#
Please find the "Samsung S3650 Downloader" from the link MultiLoader V5.67.rar