First patches are now available for Backlight 3, fast-fixing some issues in the new release.
The Publish Services plugin for Lightroom Classic is now at 5.0.1. Backlight 3 users publishing from Lightroom will definitely want to be on the 5.x version of the plugin.
If you need documentation, here’s Installing the Publish Services Plugin.
Also, Pangolin Album has been updated to 3.0.1, with an important fix to ratings stars for Client Response users.
Updates are available from the Backlight Modules page in Backlight, as usual.