Hey, I love the idea behind your mod. I'm testing it out, but I've run into a problem.
I managed to make the requests, but when the train starts moving, all the items in the wagons fall onto the ground.

That’s not ideal, appreciate the heads up let me look into it and see what’s going on. It’s all items in the wagon with nothing leftover?

Yes, I made the request via the wagon interface, and the items arrived. But the moment I switch to manual mode or send the train somewhere, all the items drop onto the ground around the train.
Could another mod be interfering?
I have several mods, but the only one affecting wagon mechanics is this one:

https://mods.factorio.com/mod/filter_assistant_adapted

I used the filter on the train because the deliveries weren't precise, and the wagon was taking up a slot with one extra item beyond what I’d requested. Could that be the cause?

Nah I don’t think it’s other mods causing an issue, sounds like my inexperience shining through. Thanks for the description, I’m going to to look into if switching from automatic to manual causes the wagon to empty out its contents.

I'll be waiting for it; I really liked the idea and think your mod is amazing.
It’ll be very useful once I leave Nauvis, and great for outpost maintenance, too.
One detail: the fact that the train only departs after receiving all the requested items works really well. That’s going to make logistics a lot easier.

Check it out now in the latest update and see if you still have the same issue. I tried recreating it but I actually ran into another bug that caused the wagon to not accept any items by hand or by inserter by marking all inventory slots as closed. I think your problem may have had a similar issue with the wagon completely wiping out the inventory slots and pushing the items onto the ground.

If this last update doesn't work just let me know. Really want this to work for my own playthrough so I'm very happy to hear from someone else that they can utilize the idea as well.

I ran a test. As soon as I set the train in motion, the items fell out, though I suspect this was just a save-related glitch (since I saved right after the error occurred). When the train stopped, the items stayed in place. When I sent it to random locations on my rail network, the items didn't fall out.

I was also able to load items manually, although the slots remained locked (with the items inside) after loading. I sent that train off as well; upon arrival at the destination, the items were no longer locked, and everything returned to normal once it got back to the logistics station.

Another point: when using the logistics wagon at a station that wasn't an outpost, I couldn't leave robots there—all the robots that had arrived with the train returned with it (I had wanted to leave some behind), though this isn't a problem. I decided to solve this by adding a standard wagon to the train, creating a mixed setup with two logistics wagons and one standard wagon. This way, I can use the logistics wagons to unload items from the standard wagon and use the standard wagon to transport the extra robots to the outpost.

It's working exactly as I wanted. Thanks for the mod.