Most Lionsgate releases use something called "Screen Pass", and I believe additional Java code protection. Using Procmon (Process Monitor) was always a good way to find the correct play list in the past but that method doesn't really work anymore since, I believe, the correct playlist appears to be dynamically modified in real time. As far as I know, DVDFab has always had a fix for these, at least for the Blu-ray 2D versions. There is actually a manual, somewhat convoluted method of properly determining segment sequence and building a new playlist (mpls) file, but I wont go into details here because it is a bit lengthy (though once you know that steps, it is not that bad). It also involves the use of some third party tools and I do it more to see if I can do it, but usually wait for DVDFab to release the fix before making a permanent backup. (And my method only works for movie only copy)
Because their Java protection schemes do change, I don't think there is a "one-size-fits-all" solution, but again, DVDFab usually has a fix; it may be a few weeks but they normally provide a fix. You did not mention any specific movie title, but they usually need a copy of all the folders and files from the disk, EXCEPT the stream (BDMV\STREAM") folder, which contains all the various video segments, including extras, previews, etc., to fix. If you mention the title they will likely ask for the files and provide instructions for uploading, unless someone has already provided that. Then just need to wait. Also good idea to provide the region since there may be different fixes for different regions. Also, rentals (which are not officially supported here) usually have a different correct playlist than retail.
As far as your last question, I believe you need to be connected for cloud decrypting and if you are not connected, then DVDFab comes up in Trial mode since it cant verify your license. Admin or staff can address that in more detail for you.
