When I manually check for updates from the Updates dialog (automatic updates are broken probably due to our firewall being very strict) I still get 5.6 as the most recent. When using SR release candidate check, I do get the 5.7.31207.07545 version as the most recent, which matches the version of the executable download in the link provided above.
Rhino checks for updates once every day or two, not every time you view the
Updates dialog box. If you don’t see updates coming down in the next day,
please let me know.
Brian
Brian Gillespie
Rhinoceros Development
Robert McNeel & Associates