out of curiosity; what is the chainline measuring in front as you have it set up ?

it might help to nail down your problem.. (edit: ok i guess you did already !)
sheldon's bb page lists the later superbe pro crankset as having a 43.5mm chainline on 111mm spindle

and to further confuse things: on one italian frame i am running a later superbe pro fd with earlier superbe pro cranks on a 112mm campy spindle (everything is mismatched !) and it still works fine