MS Physics problem, please help!

[lynxmodeller]

Hello,

I've made a model using ms physics extension and have a problem
i have a vehicle that i copied from another model but seems to be playing up.
when i press the toggle play button, this box comes up: (see attached)

any ideas? i get that its somethign to do with the script but im not sure what to change, etc.

please help!
many thanks

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