Just grabbed this since the other implementations aren't working. So far looks great and I'm excited

Edit: removed issue I was having, as it was on my end due to errant legacy straight rails.

I run a pusher configuration for my trains, 4 cargo wagons pushed by 2 engines. (So I can make stations shorter, as the engines can be on bent track)
https://i.imgur.com/uMEbESn.png (top stop has a train in it as an example).

the location they're placed is entirely determined by the rotation of the parent train stop. can you test if that power wire overhead is causing it to not get placed? Also could you make some new empty rail elsewhere and see if it works?

In your second image, the bottom loader should have placed more loaders to the right. the top 2 train stations have items in the way of loaders though so they won't place anything

keep in mind loaders are 4 tiles wide not 2, so you need room around the rail to place them (but that's not the issue with your bottom train station, I think)

Edit: removed issue I was having, as it was on my end due to errant legacy straight rails.

I don't mind testing more, do you have a discord so I could paste screenshots easier without uploading them to an external site first?

Are you in the main factorio discord? I just posted this in the mod releases channel, you can click my name there to dm me