Imported rigged suspension spring doesn't work properly

Hi,

I made a spring in Cinema 4D and rigged it.

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As you can see, it works fine in Cinema.
But the problem is that in Unity, it doesn’t work like in Cinema.

What is the problem, what should I do?

Looks like the skin weight values are being converted to rigid rather than smooth/blend. Upper spring is weighted 100 to top bone while lower spring is weighted 100 to bottom bone. No blended weights.

Looks like cinema error - not Unity error. Might there be a setting in cinema to set the skin weights to blended rather than rigid - for export, or possibly the export process is converting the skin weight values to rigid?

Top joint is going from 100% hardness to 0%. Each section of polygons I was reducing strength by 5%.
Bottom joint is the same, 100% from the bot to the top, each section of polygon reduced 5% strength.