Flipped normals inside C4D

 From:  sneather
7494.1 
I have an .OBJ model I exported from MOI to C4D. It's from client CAD, via STEP file. Oddly, I have some panels with flipped normals inside Cinema. I haven't had this happen on these kinds of tasks in a long while. I can't reverse the flipped normal inside C4D, because that breaks the normal tags, and then the surfaces are toast. So, is there a way to check for normal directions inside MOI, then flip them, if necessary? I'm really stuck here, and I haven't had much luck searching for "normals" here in the discussion forum.

Thanks!