Can't log in at http://0.0.0.0:3000 using latest Sage 10

Yes, I’m still using the beta version of 10 myself. I did try out the current master branch in an attempt to sort out your issue.

Curious to know: is there a reason you want/need to use 0.0.0.0 to visit the site instead of using the proxy address? Even in the beta version of 10, I use the proxy address to develop. I’m asking in case I’m doing something wrong XD