I've added the new material to the engineering database through General Settings --> Fluids --> New, but the General Settings --> Fluids menu still only contains options for pre-defined fluids (see picture).
How do I pick my user-defined fluid?
This is a shot in the dark, but are you positive you added your new fluid to the liquids category? Maybe you accidentally put it in a different folder.
I had put it into 'compressible liquids' rather than 'liquids', mostly because the list is ordered differently between the two menus. Thanks Amit!
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