So I was just randomly going through the multitude of old bookmarks I have saved on my computer and came across this old chestnut from the court case.
Turns out it actually reveals why Mantle hasn't received the payment of costs from Calcifer yet - the order has only just been given (on 5 April 2013, some 12 months after the trial was settled).
Looks like Mantle unsuccessfully first applied for a cost assessor back in January this year (must have filed the wrong form or filled in the wrong box), before successfully filing again in February. So, hopefully that money isn't too far away.