Gift Box for a Project

[Stroonzo (Jeff)]

For tabbed box design, there are some really great ones that have been linked on the forum in the past (including the http://boxdesigner.frag-den-spatz.de/ you suggested):

Tabbed Box Maker Plugin

This might be of use: https://www.festi.info/boxes.py/

My personal go to:

Finger Joint Box

Looks good. You may also enjoy this and similar resources: https://en.makercase.com/#/

A ton of open designs - Obrary

Not yet… I found the same on thingiverse. Too much of a hassle for me. I rather use the box generators available.