Guide to custom placing stuff on spline

[Lupos]

So while I love the curvy generator, I do think its a bit too heavy and complicated for what I ultimately wish to do. 

I just want to align walls along the spline, and I was hoping you could guide me on a simple way to get started doing this manually.

This is because I want control of the pooling and type of objects and performance is key. I also just think it'd be simpler if I could write my own.