If you are starting with an eagle library or layout, you could skip the eagle conversion script, and try converting into another format that Kicad understands and can import, like the gEDA PCB (.fp) footprint format
You can do this with
This will convert eagle XML libraries (.lbr) and also footprints embedded in XML layouts (if you change the layout file ending to .lbr),
It could be that eagle is using features that Kicad does not support within the footprint you are trying to use; for example, translate2geda can't do much with SMD pads that are polygons that is compatible with gEDA PCB elements, and Kicad doesn't like arcs on copper.
If you can get the footprint in BXL format, there is also
which can convert BXL defined components into gEDA .fp format footprints, gschem symbols, and also kicad eeschema symbol libraries.