Hi @patschworld
maybe you already know, but there is a new 8.2.0 release that maybe worth test as you are currently use the 7.8,
I was in a similar situation - Linux workstation and Macbook AIr - trying to share everything over network was bit frustrated.
My current setup is mainly managed with a Linux workstation, images are local and db is local. I’m relying on sidecar files and you can read here my suggestion in another topic.
I use a NAS also as backup the folder with all the images.
Whenever I want to use the macbook to browse the archive I can use digikam with a local db on the macbook that is reading the xmp from the shared folder on my NAS. This obsiously can be slow if the connection is not fast, but in my experience once you have synced everything, then it works quite nicely. If you want to perform some tasks like updating tags for example, then you can just write them on the sidecar file and that’s it.
I gave up trying to work on a network shared folder, it doesn’t work unless you have 10gbe connection or a specific need (e.g. lot of images, multiple users, different setups etc etc).