Hi,
This is sort of a "note to self" that I should look at some point in time but if anyone else beat me to it, feel free to take a look.
I had shelved a change and decided I don't want to keep it. There was only one shelf/version. The unshelve dialog shows my self (unshelve1.png). I clicked Delete and the Name box was cleared but the Version and the Affected files was not (unshelve2.png). This meant I could click Apply after which Subversion reported an error "Shelf 'test' not found".
If there is no shelf when starting the Unshelve dialog, it comes up empty. Clicking Apply just closes it (as with Cancel). I think the dialog should behave the same after deleting the last shelf/version.
Kind regards,
Daniel