If I modify a VCXProj file by hand and modify the ClCompile items to point to the source files using absolute paths, I am unable to use the property pages for single source files.
This only affects those source files that have their name specified by an absolute path, not those specified by a relative path.
This most easily occurs when specifying the location of source files by the means of properties, such as something derived from $(MSBuildThisFileDirectory).
The problem occurs whether the path is specified using properties or without property expansions at all.
I have not tested this with non-C++ projects.