As mentioned by “The FLIP Solver Domain is immediately returning if VTR isn’t supported in OnRegister and BeginPlay.” so maybe take a look in those functions and remove the check, see if the Non VTR path is actually working. But bare in mind Cataclysm is work in progress, even getting it working, I dont know what the right settings are to get it looking like NVIDIAs demo, and am waiting on the developer to return from SIGGRAPH to provide the settings or a test map