Caroline, I feel for you...
my posts were similar to yours, as I was (trying!!) to buy a conversion from the EWC for my wife's 6 speed Brompton, which was giving me the sweats + very cold feet...
but my problems were just lack of communication from the EWC, and the fact that I had paid a £200 deposit which in hindsight, seemed kamikarzi to me too, as the 'silence' from EWC suggested a possible bankruptcy
but helpful people like flecc and others, said that eventually I would be happy/delighted with the conversion, and lo & behold, this has come to pass in spades
even in L6 form the bike is a delight...it powers up any hill with modest assistance, at a steady 13mph, and this still brings an ear to ear grin...
in hindsight, a 2 speed would have been perfect, as one doesnt need any more
and my wife loves it, although the wait did cause a bit potential Marriage Guidance while it lasted...
my advice would be, worry not, my dear, as you will appreciate the product, long after you have forgotten the cost!....and after all, you can dine out on the misery of the story for yonks