I am sorry to take so long to get back to you my key board gave up the ghost yesterday evening and I have only just managed to get it sorted out.
I am very confused as I have been told that I cannot split the title unless there is a transferor and a transferee and they cannot be the same person - there has to be a third party involved.
Also a friend googled "Splitting the house" and it came up with a response from Joshua on Just Ask from about a year ago to someone with a very similar scenario as myself, the main difference being that I have no mortgage on the original property. That suggested putting someone else on the current deeds as joint owner and then splitting the property with me as sole new owner of the new two bed bit. This would mean no CGT or stamp duty problems.
I am probably being a bit thick but I am getting very desperate to sort this out because of the potential finance problems and I have lost confidence in my current solicitor.