Problems with Field Dominance in FCP7 project

[Anmol Mishra]

I am using FCP7 in FCS3. I set all my project settings to Field Dominance -> None

When use a roundtrip and send to Motion or STP, the stap or motn file replaces the original clip in my timeline.
I have a format problem with Cineform, essentially FCP interprets all my Cineform clips as Upper Field instead of None Field Dominance.

Is there a way I can access the underlying clips and re-render after changing the Format -> Field Dominance to None ?

I noticed that this causes some stair stepping artifacts otherwise.