Help With Bubbleking Protein Skimmer

[gulflube]

I purchased a Bubbleking Mini 180 last week and the retailer is just "too busy" to answer my question. It was shipped with a plastic bolt taped to the top of the collection cup. Where does it go and what does it do? Also I have a JBJ auto top off and when it fills my sump up to the desireable level my skimmer overflows. Any suggestions?