Modifying the .jsons you've included in rd-settings is an exercise in frustration. As far as I can tell, it does not work correctly. I may be doing something wrong, but I don't think so. An example:

1. I add a mod item to the bottom-most section in the loot-all.json and crank up the spawn weight and quantity. Upon checking the loot in a dungeon, that item is successfully spawning all over the damn place.
2. Next, I add another item to spawn somewhere in the loot0.json. Upon checking the loot no mod items are spawning anywhere. Ok great, I'll revert the changes I made to the loot0.json and go from there.
3. Upon testing again for a third time, none of the items added in loot-all.json are spawning anymore despite being back at step 1.
4. Rinse and repeat for countless hours while tearing your hair out wondering why items sometimes just refuse to spawn.