> It sounds like ZTreeWin treats one-way Mirror as two separate steps:
> 1. copy all unique and different files,
> 2. delete all files unique to the target dir.
>
> and ESC only cancels the first step.
>
> IMHO, this should be classified as bug, not ZEP; it’s not the
> expected result of pressing [Esc]ape: in the UI, Alt-Mirror is treated as
> a single operation, so pressing [Esc]ape should cancel the entire
> operation, not just the first part of it.

I agree, but at what stage does it do the deletions? If they happen at the start then they're gone and may not be retrievable. It probably should at least report how many were deleted, and maybe which ones. If it does them first, I guess that could be changed to do them last.

I've never used the sync options before, and I'm a bit horrified at how easy it would be to make disastrous mistakes with it.

If you use a two way sync with the wrong destination, I assume that could make a mess by merging the source and destination files/folders? No deletions, but a mess that might be very hard to clean up.

Perhaps both sync options need to display a summary of what they're going to do. Eg:
"4926 files and 200 directories will be deleted from the destination branch because they don't exist in the source. Do you wish to proceed? Yes/No/List"
or
"597 files and 22 directories will be copied from the destination to the source because they don't exist there. Etc"

Can robocopy create disasters like this with its PURGE option?