Assembly Save as Part, Exterior Faces only

Because I'm working with Sub assemblies with around5000-10000parts I want to save these assemblies as a static part soI can usethese  Parts" in Top level assemblies.
When I save the assembly as a part with the option exteriorfacesonly and all settings high in performance I get when I openthePart that a lot of faces of fasteners and corners of sheetmetalare not displayed. What can I do to solve this ?

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Solidworks 2007 (64-bit) SP3.0
Windows XP Pro (64-bit)
Intel Core2 Duo 6700 @ 2.66Ghz
4Gigs DDR2 Ram
10Rpm Raptor
SolidworksAssemblies