Just to keep you on your toes, MSFileReader provides the exact same
files as Xcalibur (Xrawfile2.dll, fileio.dll, fregistry.dll), but
they're not interchangeable. One is in the Xcalibur namespace and the
other is in the MSFileReader namespace. Or whatever COM calls it when
the object is identified by "MSFileReader.Xrawfile.1".
Msconvert doesn't require COM (regsvr32) registration, and pwiz is able
to redistribute the DLLs in the binary archive now: a separate
MSFileReader installation is no longer necessary.
If you've registered Xcalibur's Xrawfile2.dll with regsvr32, readw
should work. Otherwise, it won't.
-Matt