The file was not stripped, if so you would might have found your “issue”
First impression: the ExtrudeNURBS hierarchy, (see image). An extrudeNURBS can’t be a child of an ExtrudeNURBS!
BTW, if you have splines which produces the information for an ExtrudeNURBS, set the intermediate points to something that matches the Cap “resolution” and you get not these long triangles in your animation. I would avoid N-Gons for this kind of animation as well.
In the moment you have set everything switch the PolyFX off, run it one time and then from frame zero, switch it on. It should hold then no informations from the previous set up. I went three times along with this idea and I got stable results.
All the best
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