LI ALEX

This is really great.

Here are some errors after my test:

1.I define login.mysite.com as root site of Userswp in config.php
2.once it is network activated, it will redirect to a error page: http://prntscr.com/iu2uaw
3.refresh that page, I can access dashboard, and it is already activated.
4. go to login.mysite.com/wp-admin, it will show a white page with a debug error:http://prntscr.com/iu2v03

so I have to deactivate it, let me know how to resolve.

FYI, wordpress 4.9.4, HHVM+ Redis cache, and PHP5.6.33