Write to [email protected]. Please say which device and which version of the system you are using.
No. Lightbrary needs only access to your photo library.
They come from the optional Lightbrary Exporter, which runs on the Mac that holds your photo library and passes them to the apps through your shared iCloud Drive folder. Browsing, rating and pairing up work without it. See the manual.
Stars and marks for deletion travel through iCloud Photos. Everything else goes through the shared folder: each app checks it when it comes to the front and every two minutes. Make sure every device and the Exporter use the same folder, and give iCloud Drive a moment to upload. sync now checks straight away.
Into Recently Deleted in the system Photos app, where they stay recoverable for 30 days.