PayPal – blank screen on “step 2”

Hello!

And happy new year.

I am struggling through the PayPal configuration for a website I am working on

http://www.communitycrowdfund.co.uk

I think I have set up the PayPal details correctly, but when I enter details to fund a project on the site, when I press submit I get a blank screen on the “step 2”.

I found in a previous post your PayPal details for a test case and it seemed to work fine?

Any ideas?

regards
Tim