The OP has a double crank; I don't think it's asking too much that the inner chainring of a double crank has access to all cogs in back. (Edit: Granted, depending on the geometry of your setup, it may not be possible.)

I have no experience with Campy, but aren't their front shifters quasi-friction with multiple positions to somewhat-fine tune the derailleur?

I would disconnect the cable and start over. Make sure the FD is as parallel to the chainrings as possible. Set the low limit screw so that the FD inner cage gets as close as possible to the chain while in the little/big combo without rubbing.