I just detected a little issue with uint32 which is declared in the JUCE_NAMESPACE and is not accessible from certain files.
#define uint32 JUCE_NAMESPACE::uint32
#define uint8 JUCE_NAMESPACE::uint8
in the files that give compilation errors (FilterGraph.h, juce_VSTPluginInstance.cpp) , does the job.
BTW the 10.5 SDK and the Architecture (i386) also have to be changed in the project settings.