This plugin broke my website

After an SEO review I discovered I have hundreds of broken links. I thought this plugin would save me time. First thing after installing the plugin, I had a database error. I called my trusty web host who thankfully has telephone support, and they said that mysteriously the site had been pointed from the subdirectory where WP lives to the main directory. We fixed that. Subsequently the formatting of the page went crazy, and then I was unable to log into the site at all.

I assume that there was some sort of incompatibility problem with other plugins I have running, but use this at your own risk. It cost me several hours of productivity.