Ores that would normally require fluid to mine, are now mined normally, but need to be washed with corresponding fluid. Designed for use with Angel's infinite ores, RSO, Bob's and Clown's mods.
It appears that these mods are not compatible: raw (unwashed) ore can be loaded into the "bulk loader" but is not moved from there to the railcar like other ores. https://mods.factorio.com/mod/railloader
Create a new game with the same mods and send me the "empty" save file, so I can have some kind of reference. You can pm me on the forum with the save, or upload it anywhere and post the link.
@leoch, Quick fix for this is to change map setting for bulk rail loader->allowed items=any, instead of the default =ores.
This doesn't solve the compat. issue, just makes it work so you can play until a fix is made.