This plugin has been closed as of December 24, 2018 and is not available for download. Reason: Guideline Violation.
Looks like Happy Nuclear is defunct (home page now a japanese hair removal company?), but product still working well for my simple purposes (creating multiple new users with passwords, up to 100 at a time). I've used CVS import method several times, seems to work perfectly. Too bad no one is maintaining this product.
Luckily I found another plugin that did work.
All you need to import or create user from a CSV, a list of email or manually. Fine.
Contributors & Developers
“Add Multiple Users for WordPress” is open source software. The following people have contributed to this plugin.Contributors