Hi Steve
I've just checked the membership pages and it seems to be working OK for my test account.
When you say it just stops at membership details, is it giving you any errors? Have you filled in all of the required fields?
I'll be offline until about 8:30, but should be online after that so please feel free to message me.
As an aside, what browser are you using? I have tried it in Firefox 31.0, IE11 and Chrome 37.0 and it works fine.
Please get in touch so I can help you out with this issue
Regards
Simon