Ah yes the staircase is a great starting point.
The main thing I want to change is to ALWAYS have the treads the same height, regardless of the angle of the spline.
You can see that the stairs using the shallower angle in the screen grab have shorter treads. I'd like to always specify the height of the treads.
Maybe I was trying to find a convoluted way of doing this but I assumed that starting by outputting the angle of the segment driving the stairs would then allow me to adjust the height of the treads via expressions.
Probably totally over complicated the approach and hence very confusing

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Thanks for persevering Dragan!