I used roughly 3 hours of my time tonight going through my mod list and testing for incompatibilities. Here is what I found;
--AAI Vehicles: Pretty much all of them generate an error on line 166 of data-updates.lua
--Deep Core Mining: Recipe error, unsurprising really.
--Heavy Tank 2°Gen: No liquid recipe generated for the final version of the scrap tank, unknown if any other components were unable to be translated.
--Modular Turrets: No liquid recipe generated. This one is kind of a deal breaker for me.
--Orbital Ion Cannon: Icon error. Not sure why.
--Portable Power: Icon error.
--Schall Tank Platoon and Vehicle Turrets Mods: Don't remember if this was a recipe error or icon error, leaning towards the later.
--Vehicle Wagon: Icon error again.
When I started seeing these errors, I figured Iron Man and Robot Army would suffer the same fate, oddly they didn't and seemed to work okay. All the errors above prevented the game from loading and gave me the choice to disable Fluid World or all mods.
The list of Mods I have that did work, if that even helps; Alien Loot Economy, Armor Plating, Assembler Ingredient Restriction Removal, Asphalt Roads, Better Bot Technologies, Big Brother, Bio Industries, Bullet Trails, Canal Builder, Concrete & Stone, Dyson Swarm, Early Construction, Easy Refinery Recipes (again surprisingly didn't break the mod), Electric Train, Factorissimo2, Iron Man, Laser Beam Turrets, Lighted Electric Poles+, New Game+, Noxys Trees, Opening Logistics (my personal mod not submitted), Picker Pipe Tools, Quick Charge Personal Bots, Robot Army, Texugo TA Miners, Texugo Wind Generators, Turret Shields, Useful Equipment, Vehicle Grid, Vehicle Snap, Warehousing, and Wood Gasification. I have more mods but they were the kind that didn't seem to gel well with Fluid World by their very purpose so I didn't bother trying to enable them.
Hope this helps. Great mod otherwise!