help with w850i firmware for unlocking

HI i'm new to this and could do with some help/guidance to unlock my W850i.
I have simox sim-lock patch generator v2.1 and have read the tutorals but
I am unsure about the exact firmware to use to generate the patch? If
some kind soul could tell me the exact firmware number or point me in the
right direction I would be most grateful. The phone details are as follows.

It was bought in the uk and will be used in the uk.
currently locked to "3" network.
Current firmware version R1ED001.
EPROM CID 52.
EPROM colour RED.
DB2020 CID52.

Thankyou for any help.

Read here : Flash your phone and How to apply or remove patch using SETool 2 Lite - Top Sony Forums and post the identify log here