I wanted to delete two lessons that were mistakenly imported but I encountered a page indicating “500 - Server error” just after clicking “delete”.
My browser is Fire Fox 12.0.
My computers’ OSs are Windows 2000, Windows 7.
As you have many tasks to do, I think this is a minor issue. I hope that you will be able to solve it in the near future. And thank you for a great improvement. ( This new version is very effective for me.)