I downloaded http://sites.google.com/site/zigmar/notepad2withluasupport source code, opened it in VS2008 and when compiling I got
Error 1 fatal error C1083: Cannot open source file:
‘.\scintilla\win32\ScintillaWin.cxx’: No such file or
directory c1xx Notepad
whereas \scintilla\win32\ScintillaWin.cxx does exist as source code project files.
So why ?
I downloaded the sourcecode from the link you provided, however in the project the file is present, in the zip/directory tree the scintilla directory is empty.