In the first picture on the mod page, there's power poles placed on landfill in the middle of the sea to power pumps and unload tanker ships. I can't for the life of me figure out how to place landfill near where wooden platforms are required, or how else to power these pumps. Is the idea to only build waterways so close to land that regular power poles will reach? Or only use cargo ships full of thousands of barrels for land-based production? Or maybe I'm supposed to wait until I have foundation to use tanker ships?

Its not Middle of the sea
Its right next to an island on shallow water

Is the idea to only build waterways so close to land that regular power poles will reach? Or only use cargo ships full of thousands of barrels for land-based production? Or maybe I'm supposed to wait until I have foundation to use tanker ships?

So:
- Offshore oil rigs can produce power. Enough in fact to power up some machines ins mall radius around then (hover over oil rig powerpole to see radius). This is done so you canuse tankers with oil rigs without any landfill or foundation, place lamps, maybe some inserters etc.
- electric pumps can be placed on water and wooden platform.Diesel pumps can't. This is done this way to prevent pipelines, because diesel pump can essentially power itself.
- early game revolves around heavy barrel usage for transporting fluids, later you unlock tanker, and then titanium barrels. Tanker and cargo ship full of steel barrels have the same fluid capacity, but tanker is more convinient. Titanium barrels allow you to essentially double cargo ship fluid capacity, but its not as convinient as tanker so people stick with tanker.
- you can only place landfill and sandfill on shallow water. Shallow water is naturally present around the islands, and every ground you dig up with channel excavator becomes shallow water. Ships can go in shallow water so no worries. My recomendation is to dig channel or trim some of the island to have place to load and unload ships.
- main source of power on planet is liquid fuel, and you can just ship it on islands that need it.
- unless you were rly unlucky with terrain gen you can complete first landing with single island and 2 oil rigs
- after completing first landing you unlock tools for expansion such as delivery drones, tanker, cargo crates
- idea for expanding and base is to create archipelagos of interconnected islands. Where one island specialize in production of certain stuff. So you have sealant island, ethanol island, coal processing island etc

Not sure if that fully aswers your question but thats all I could think of right now that you might want to know. If there is more feel free to ask.

Thank you for the rapid and detailed response! My confusion stemmed from only being able to place landfill MAYBE a few tiles off the coast of the island I landed on. It wasn't until I scanned around to other islands that I saw that some of them have huge swathes of shallow water of their coasts. It was just bad luck for me.

Your breakdown was great. The tech tree progression outlines what you said, but having it written out was the confirmation I was looking for. Five stars, zero complaints, I'm looking forward to heading back to the planet and seriously scaling up. Thanks!