This is the setup:
1) I have an SWF in which I have defined a component in the library with a custom class as the linkage. The component has been set up for "export for run time sharing"
2) I have an fla where I copied over the component and linked to the first SWF via "import for run time sharing". This fla will be published as a SWC. The content of this fla resides in a movieclip to which I give a linkage so I can instantiate it in the app that has the SWC in its lib path.
3) I have a flex application that has the SWC added to its library path.
When I run my flex application, my RSL component does not work at all.