I'm sorry V2C for the (now-seemingly) unnecessary mention I did in the cavespreview's thread, seeing as there are already some cavespreview related bugs in the bug tracker. I can't take it back cause the notification is already sent. Sorry about that.
So about this bug report, if you generate a world using a saved cave custom preset for the cave's portion of a multilevel server, the server will generate SURVIVAL Mode Level for the cave's level.
Master (overworld) and Slave (caves) logs attached found under (Documents\Klei\DoNotStarveTogether\Cluster_1):
1. Toggle any preset option in the cave's tab under the Multilevel World tab 2. Save the preset 3. Generate world with that saved preset for The Caves tab (i.e. Custom Preset 1, 2, etc.)