I have been using DT Pro Office for the past few weeks, and these days quite intensively in order to gather and keep material for a book which I am currently writing.
It proves quite convenient, but I have noticed one serious problem - which I assume will however be fixed easily.
When I delete one or several individual documents, I get a warning - if I have made a mistake, it is still early enough to go back.
But it has happened to me thrice today to delete by mistake an entire category with all its content, and I have discovered that there is no way to go back (unless there is a recent backup - fortunately, I do backups every hour, and sometimes in-between) and - worse - no warning. I have looked in the preferences, there seems to be no way to activate such a warning - and no trash box from which to recover some category deleted by mistake.
Twice, it happened as my intent was to delete a document, but for some reason the category got deleted (although the document seemed to be selected on the screen, that was quite perplexing - I just wanted to suppress webpages which I had saved as web archives).
Anyway, I do strongly advise to introduce - at least as an optional feature - the ability to have a warning before deleting a category. I feel this is a crucial issue.
I thank you in advance for considering that request. Is there a trick to implement it already?
Otherwise, I have come across no real problem up to now. (And I am also glad to report that restoring from backup after my accidental deletions went flawlessly.)
There are currently only two workarounds to avoid losing data by accidentally deleting a group.
The first one you’ve already discovered. That’s to have a current backup.
The second one is caution. I learned that one a long time ago, when doing laboratory research. 
You might be surprised by how many users have requested a means of turning off the warning when deleting documents. Personally, I prefer the feedback.
A future version will allow recovery from the Trash. (That’s currently true if one deletes a PDF, postscript, image, QuickTime file or Imported “unknown” file types, but some associated metadata can be lost.)
Thank you! Glad to hear there will be a way to make a recovery from the trash in the future, that would indeed solve the problem.
And please, keep the warning! If people really want to have it removed, just make it optional, but keep it by default, it is really useful.
There’s no warning if your deleting either an empty group or just some replicants (in both cases you’re not deleting any data at all).
Well, when it happened to me those past few days, it was not empty groups, but groups with content. And the originals were already in the trash. I still don’t understand how it could happen, especially since - in two cases - I am sure I had not selected the group, but individual items, and suddenly the category was deleted instead of the items - it was like the group “over-riding” the items. This is why I posted about the problem in feedback, and not in troubleshooting - I wondered if it could be a bug in rare cases? Since it did never happen to me in months of use of DTP, and suddenly happened three times using DTPO…
But OK, I am a human being, thus fallible, and possibly I made some mistake without being aware of it.
If you’re able to reproduce this problem, please let me know.
Sure, I will! Also in case I understand what my mistake was, if there was one.