The component is either contained in a .SWC or it is source
code. If you have a .SWC, place it into a directory and included
the SWC in your Flex source path. From Flex Builder, pick Project
Properties->Flex Build Path; chose the Library tab, pick "Add
SWC" button and navigate to the SWC file.
if you have source code, then pick Project
Properties->File Build Path, chose Source tab, and add the
directory of the code.