Here's a screenshot of what the baluster looks like in my project. I'm also attaching a copy of my baluster family.

I'm starting to wonder if someone's messing with me -- where's the camera? :hide:

Your baluster doesn't appear to be unique or different from the stock square baluster. Why not just use that? Have you compared it with your work? The angled reference planes in that template and baluster families are "special" because the "factory" put them there and Revit must be doing something internally to interpret the angle properly when it changes for stair or ramp rise/run.

I have 2 OOTB balusters: square and round. My baluster is 1x2 and the square one only allows one dimension.

I opened your baluster family, locked the profile to the line. Worked fine.

I have to guess that you're talking about Align the sloped line in the extrusion with the top cut reference line/plane and then lock it. I did that and it didn't work for me.

Here is the family after I edited it.

This is getting really strange then. I tried it with your baluster and it still doesn't work. In the attached project file, I have nothing except the stairs/handrail shown in this screenshot. As you can see from the screenshot, I've still got horizontal tops and bottoms on the balusters.

Looks like they are offset from the railing, if so there is nothing to cut off the ends. Cut a section or look at the stair from the end to see how they are lined up.

Yes. They're offset -- that's how they are in real life. In real life, they're exactly as I've shown in the screenshot except for the fact that the top and bottom angles are parallel with the stringer. They're nailed to the sides of the stair stringers opposite the treads rails -- and there is a "Handrail" sitting atop the upper rail. That's why the profile looks as it does.

I had hoped that they'd still pull the angle from the handrail.

I manually calculated what the angle should be (the stair slope should remain the same throughout every instance of this stair type). I then edited the extrusion in my baluster family so that it wasn't locked to a reference line -- it was just drawn at the angle that I need (basically eliminating it's parametric ability). When I attempted to use it with my handrail, all I got was "Can not create baluster". Of course it doesn't tell me WHY it can't create the baluster. It flexes fine when in family editor.

So how would you recomend modeling this handrail?

EDIT1: I've since created ref lines locked to the desired angle and then locked the top and bottom of the baluster to the ref lines and it still throws the error about can't create baluster.

EDIT 2: Corrected a mis-statement (see the strikethrough).