A random test had me using the Muttiple Models on a Path wizard and unfortunately I get a crash each time I attempt it.
Perhaps someone can verify?
Create a simple model (to be placed on the path in the chor).
In the Chor window create a Path
In the PWS select the Path and Right Click (the only option should be Multiple Models on a Path)
Follow the instructions and select your model and apply.
At this point A:M crashes for me.
Edit: Figures... as soon as I post I thought to check to see if the v18 MMoP.hxt file worked in v19... and it does.
So, that would be the workaround if the v19 MMop.hxt is corrupted.
The file that isn't working is dated 2/6/18 and the one that is working for me is dated 5/25/15.