[Plugin: Redirection] can't create redirects, groups, or modules in multisite

Just installed Redirection 2.1.29 again now that it’s compatible with 3.0. Yay! However, I can’t create any redirects or groups.

On creating a group, I type the name and hit “Add,” and I get an error saying I have to enter the group name.

On creating a redirect, I enter the paths, leaving all other settings on their defaults, and hit “Add Redirection.” I get an error saying “Sorry, but your redirection was not created.”

On creating a module, I get “Your module was not created – did you provide a name?”