Dear friens:
I am evaluating the NWC in my XP window. When I try to open a MIDI file appears the next message: "There was a problem with the file". And when I open a NWC file created by another user:"This file failed to open. It either does not exist or may be corrupted."
My guess: MIDI and NWC files should be downloaded as "binary" file type. This should happen automatically. But sometimes, the file server (or your browser) does not understand, and downloads the file as "ASCII" type.
Which browser were you using, when you downloaded the files? If it was not Internet Explorer, try downloading the MIDI and NWC files again, but this time use IE.
If that does not help, the problem may be something else. But certainly the NWC program can open MIDI and NWC files.