I've used this to make tabs for the Merlin, a DAD instrument strung in the mirror image of the mountain dulcimer. Like many similar prgs has a bit of a quirky note entering scheme, but it does work well.
It was my favorite tablature editor a long time ago. Besides not being an adequate replacement, my choice today is musescore with an extension to display the guitar fretboard.
if you are comfortable with the LaTeX style editing, lilypond is an amazing editor and layout engine for scores that can produce tab or traditional sheet music output (and fretboards for fretted instruments or most anything else you could want)
Haven't tried yet. I don't think it will still be adequate since it follows an workflow that requires precise knowledge of tempo and rhythm before knowing the melody which is simply not how "my brain works". But since I use it mostly to listen repeated parts of a new music I choose to learn, it is certainly good enough for my needs.