How do I change the teference proxy field

Assuming that you are using the terminology correct and you're asking how to change the reference proxy field and not the actual reference field itself, then you just make sure that the field that you want to become the reference proxy field is indeed a look up field on the relationship and go to the field for related parent and make the change there on it's field properties.  

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Mark Shnier (Your Quickbase Coach)
mark.shnier@gmail.com
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