Shadow catcher or another method?

[jmillerdesign]

Hello,

I've been using C4D for awhile, but fairly new to Corona and I can't figure out how to make the shadow catcher work for me.

I've got a model, against a white cyc background and I simply need to be able to composite the item with alpha masks for each part onto a transparent background with shadows. When I try and use the shadow catcher, the shadows are incredibly dark and my model doesn't render well without the white background reflecting light. Maybe I'm going about it completely wrong :(

Any suggestions? Huge thanks for the help!