I purchased mine in 2011/12 and it is still going strong, although they might be using different cells now:
http://www.pedelecs.co.uk/forum/threads/bmsbattery-sucessful-purchase.10082/
Most comprehensive one I could find, it is a shame no one imports them, but the minimum order is for 10 off:
http://qyyebike.en.alibaba.com/product/60215732351-209543290/unique_design_folding_electric_bicycle.html
See search results below for "motor mounting bolts":
=2']http://www.pedelecs.co.uk/forum/search/355007/?q=motor mounting bolts&o=date&c[node]=2
is it these threads?
http://www.pedelecs.co.uk/forum/threads/the-kalkhoff-klunk-a-problem-with-my-agattu.14915/...