I believe that crypt should be able to handle ranges now and should allow cache to properly read partial files through it. But I only believe, I want to properly test that before actually making that a certainty.
I’m also working on storing the frequency of reads for file data. That means the cleanup process will favour file data that is less read over more “hot” data. What that translates to: Plex scans will result in a persistent cache as long as the total cache size is enough for all the metadata scans on your libraries. Cache will then just prefer to clean data cached from playback.
But this after the 1.4 release