YOU NEED AN UNDO BUTTON!!!!!
I was using this program for an outline for a research speech for school. I was almost finished when all the text was highlighted and something popped up and said "this task has been performed...press this button to undo". I pressed undo thinking it would unhighlight the text, but instead deleted it all!!! I frantically tried to get my speech back, but since there is not undo button, unlike other programs like Microsoft Word, I was unable to do anything. I spent a lot of time googling to find a solution to my problem, but found NOTHING. This research speech is a 7 day project and I now have to start over with less than 2 days to finish. ALL MY RESEARCH AND EVERYTHING IS GONE THANKS TO YOU. I will most definitely not be using this program ever again.
Jean-Francois Joly commented
Definitely needs an undo button or some way to view changes through time. I just blew away a whole node (not sure when exactly, I just happened to see something was missing) and I have to way to restore it.
Sorry for the problem.
If the items were deleted, please try 'rd' keyboard shortcut for 'resore deleted' command - you might be able to restore items.
If this won't help, please let me know to firstname.lastname@example.org and send URL of the list with the missed data - we'll try to find out what can be done.