I have the same problem as this user!
Iam using the latest version of your Ning-to-Wordpress plugin, the latest version of Buddypress, WP 3.1.1 and use the WhiteHouse theme from Pagelines. My ning-files folder is was FTP’d to the server. My Ning export contains 376 members and a nominal amount of content.
I started the import process. Members imported properly and required a few refreshes. Profiles imported properly.
When the plugin got to the Groups import step, it hangs. The text message instructs me to hit refresh a few times and click the “Continue” button. There is no Continue button. As a result, I can’t finish this step and can’t move on to the next step.
The most important thing for me to be able to import into my WP site is the blog posts and their comments.
Your guidance would be greatly appreciated!