Its quite hard to follow your posts.
You say that the charge was removed and a letter had to be sent to land registry to vacate the mortgage.
But then you say you still owe the money. Which begs the question- why was the charge removed?
And there's no point just asking for a specific answer to this specific question-
"All I want to know is can they simply be added when there is no existing burden?"
when there is something else going on in the background.
If I assume, for a moment , that there was an administrative error when the charge was removed, and the money is still owing, and you're in mortgage arrears, then I will assume that Start will make moves against you and attempt to put right what's gone wrong.
mf