"Error occurred" message

Erwin,
Very, very happy to hear that! I just sent you a friend request on Facebook. Please accept it. Then, I can add you as an admin to the app.. then, you can remove me from the app.. then, hopefully, all is well.

If that does work, we can help you create other apps in the future. Also, let us know when you've transitioned it over to you. I'd like you to submit a bug report to Facebook about your issue. If you can simply leave one 'test' site up with the 'old' api key/secret and the 'new' working one, it will be easy to demonstrate the issue. I can give you all you'll need to post, but you'll need to make it from your account. Hopefully, that will help it get fixed for future apps you create.

Thanks,
Alex