If the TARGET and directories have the '' character in their name, the link between the sln and the vcproj file is not done properly because during the vcproj generation the filename is untouched, while during the sln generation the '' is replaced with '_'.

msvc_vcproj.cpp,553: QString vcproj =
unescapeFilePath(fixFilename(tmp_vcproj.project->first("QMAKE_ORIG_TARGET"))
+ project->first("VCPROJ_EXTENSION"));

by line

QString vcproj =
unescapeFilePath(tmp_vcproj.project->first("QMAKE_ORIG_TARGET") +
project->first("VCPROJ_EXTENSION"));

• The compilation option MP, available since 2005 is not taken into
  account:

msvc_objectmodel.cpp,649: added:

}
else if (second == 'P')
{
if (config->CompilerVersion >= NET2005)
AdditionalOptions += option;
else
warn_msg(WarnLogic, "/MP option only for .NET >= 2005, ignoring.");
break;
}