Registration form hangs in Google Chrome 12, IE 8

I have a clean install of WordPress 3.2.1, with Membership 2.0.7 on WampServer 2.1

I followed the tutorial here:

When I fill out the registration form and submit, the submission never completes, but a user is still created, but not activated or added to a subscription.

I assume the next page should be asking me to click the “Subscribe” paypal button setup under “Free Subscription” gateway, but it never gets there.

How can I resolve this? This is my second clean install, with the same problem…