Help: How to fix it: attempt to index nil with 'ClassName'

Help and Feedback Scripting Support
#21

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#22

how to use this weld plugin:
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#23

All of the parts is:
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#24

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image939×364 77.3 KB

primary part:
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image321×592 22.1 KB

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image323×588 22.5 KB

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image330×584 27 KB

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image326×559 21.5 KB

#25

Works when I unanchored all parts: