Thanks dx100uk. You are indeed correct, the original lender was Future Mortgages. I have every statement, Engage sent me them without me even taking the statutory fee. There's been communication between us, always in writing, and they haven't said no to any refund, they've asked me to write to them with 'what I think the total amount of charges are ', they also stated in their letter that Solicitors fees can't be considered.
I've tried opening said spreadsheet, but I get a 404 error, I'll certainly try the other one though, thanks for the reply.