I originally posted this on Turbine's Forum:
Posting it again here for you guys..
Just thought I would post this to help with some people who may be suffering confusion and stress with the migration tool..
Step 1 will ask you to confirm your Codemasters account details.. If you enter this and get an error or server down message, wait a minute then go back to the beginning and start again.
If you manage to get to step 2, you will be prompted to create a new Turbine account.. The username needs to be unique, if you want to you can use your existing Codemaster username, however if that's taken you will be asked to enter another.
The password must contain a character and a letter.
There have been some reports of players unable to create an account under the age of 18, if you are under 18 perhaps ask a parent to create the account for you.
After Step 2, if you submit and get an error or server down message, before you go back to the beginning and start over, double check your migration process as it may actually have gone through.. Whilst there are three steps, the third doesn't need to be completed to migrate your account.
Try logging into Turbine's account site at https://myaccount.turbine.com/ to double check. If you are able to log in then your account is migrated and you can create a sub if you need to. Lifetime memberships do not require you to create a sub, however you may want to attach a credit card to your account for future store purchases - this is not compulsory though.
When you want to attach a credit card, be sure your address details are 100% correct, including the region.. A slight difference will possibly cause errors with your card company. I know this sounds basic, but I had problems because I had London selected as my region rather than the borough I live in.
I can't actually comment on as I've not got this far on either of my accounts even though they are both now migrated.. This step asks you to create a sub, if you have a lifetime account you can skip this step, otherwise you will need to create a new subscription if you wish to play as a VIP.
When all this is done, open up your EU client which will begin to patch.. When the patch is done you will be prompted with a grey box asking you to enter your new Turbine account details, do this and click continue. The client will verify your account, and as long as this is Ok the client will then ready itself for you to log in.
The EU servers at present are offline so you won't be able to log in and see your characters just yet, but you can enter the previous US servers if you want. Note also that your points won't be available right away, you will have to wait a while for those to follow.