Why is the Instabuild Option not available for all Parts ?

A Component i need a Symbol/Footprint for is not available thus i wanted to use the Instabuild Tool to create the CAD Symbols not only as its very convinient but also since i would have the symbol available for Kicad and Eagle without creating it manually in both CAD tools. I was wondering how to Start the build tool and after watching the inroduction Video i noticed that the option is not available for the component i need even though there is already entry for it but only the datasheet is available. I can launch instabuild from the example Parts but there is no way to change it to another component. Why is instabuild not available for every Component or is there something i overlooked ?