I wasn't aware that people already developed solutions for Zen-Cart button generation. So I had developed my own. Good news for you is: I released this as open source into the Zen-Cart community. So you can adjust that to cover your own specific needs, like adding another language, your own button templates etc. Only restriction with the package is: you are not allowed to distribute this development in commercial packages or use it on public websites that advertise your services.
This package doesn't have such a fancy interactive GUI like the Buttonsworkshop. The advantages of this package are: You should get designer quality results very quickly. E.g. the routines for the text output have been optimized for better text rendering and kerning. There are some text effects too. And you can overlay icon sets over the buttons to visualize button functions.
See a demo here (might not be online forever):
http://zen-bck.mediakitchen.de/
It has no advanced features for downloading the resulting button set as the tool was not originally meant to be used as a public online service, but you can use Firefox's 'Save Website' feature to download the whole results site for example. Be aware that whenever someone else is using the demo at the same time that your results will get overwritten on the server.
Download the open source Zen-Cart contribution named 'Zen Button Construction Kit' here:
http://www.zen-cart.com/index.php?main_page=product_contrib_info&cPath=40_44&products_id=743
For that to work you will have to bring your own TrueType fonts and you have to install it on a PHP/GD/Freetype enabled web server. But then you can tweak to your hearts content.
Hope you like it :)
Best regards,
Sir John Steed