'analytical data' showing up when importing revit structural model into Navis 2013

I have recently made the move from working with Navis 2012 to Navis 2013. As such i am now importing the designers revit 2013 files direct and combining in Navis manage. The architects models seems to import OK, but the structural model dispays duplicate concrete walls and slabs as 'analytical data' This data is displayed almost as a 2D element in the 3D environment ( the object is there as a solid object, but there is no depth to the object), located in the correct position. This data is not present when other disciplines are viewing the same revit file, but in revit. Does anyone know what is causing the information to be displayed in Navis.There is also alot of structural 3D elements missing when i import into Navis, that are present when viewing in Revit. The scheme is made up of 3 very similar buildings, 1 of the blocks dispays the strutural walls/slabs as a 3D element, whilst the other 2 blocks only display the analytical data mentioned above. I have spoke to the guy who did the modelling, and he said he modelled 1 of the building (the one that is displayed correctly), and then 'copied and pasted' it for the remaining 2 bulidings. It is these 2 bulidings that are only displaying the analytical data, and no 3D objects.I would be grateful of any help that anyone could offer. I have tried changing the settings under the 'revit file reader' option to 'whole project', this seems to fix the structural issues in so much that the 3D objects appear, but then creates an issue with the architectural model in that a whole barrage of information is now displayed called 'masking' information,