Adds massive cargo ships to the game, that function similarly to trains. Also adds deep sea oil, oil platforms, tanker ships, train bridges and other water based content.
Is this new after the last update? Please post a screenshot or a save file. There should be a ship-loading pump attached to the oil rig, correctly aligned to the waterway.
So the right side works and the left side doesn't? That is working correctly.
To have an oil rig fill a ship, you have to align everything correctly: 1) place waterway, 2) place ship pump on the water so that the waterway is highlighted, 3) place oil rig so it feeds the pump directly. (If you place the oil rig first, it might not be aligned to the rail grid properly.)