I would check the optimize for printer and set your default printer. I
think that this would give you a visual as to where the report is going to force the margins to be.
It could be that CR doesn't believe your printer is truly edge to edge and so puts in a default...but when it comes to these types of issues, I don't really have expertise...I would just try to work inside the parameters that CR is telling me it is going to do.
Frustrating I know, but what is there to do? I guess you try and talk to CR tech support...if it requires a programming change the effective date to get the fix is months away.
HTH