Hey! Sorry for the delay!
To make these files work with newer versions of the FXMaster module, I removed the default particles behavior from the scene files and instead included a macro file that you can import (using the same steps of the scene files, but inside, using a new macro inside the macros folder) and activate the underwater effect when desired by clicking it.
You just have to download the files again and import what you need. The macro file is included there also. Or, just copy and paste this into a new script macro:
Hooks.call('fxmaster.updateParticleEffects', [{"type":"bubbles","options":{"scale":0.8,"speed":0.5,"lifetime":1,"density":0.05,"tint":{"apply":true,"value":"#6e8891"}}}]);
FXMASTER.filters.setFilters([{"type":"underwater","options":{"speed":0.3,"scale":4}}]);
(But you'll also need to re-import the scenes, or else it wont work.)
I hope this helps! Thank you for your support.