Try an offset from the solid file I provided. You should be able to do the offset including the rounds.
To fill in two of the rounds is not a problem with a simply extrude of the edge.. However, the integration of two surfaces for the 3rd is little more tricky.
I have the original offset at 10.2mm form the original surface. Is this still the case and is this also a 2mm thick part making the "inside" 12.2mm from the original surface?