Due to a bug in OS X 10.4.7, Nisus Writer Classic documents lose their own icons and their association with the Nisus Writer Classic application that created them. If you select one of them and look at the Finder's Info window, you'll see the default open application has changed to something else, most often TextEdit. So double clicking on a Nisus Writer Classic document will start TextEdit and open the file there. For a single file, you can change back the default application to Nisus Writer Classic but Change All does not work. This is a very annoying situation.
As a work around (until Apple resolves this bug) we offer a little intermediate application that was developed by our long-time power-user Kino in Japan.
1. Download the file DropOpenWithNW.zip and expand it on your hard drive.
2. Choose one
of the files in the folder (depending on what version of Nisus Writer Classic you use):
DropOpenWithNW513.app for Nisus® Writer
DropOpenWithNW603.app for Nisus® Writer 6.0.3
DropOpenWithNW65.app for Nisus® Writer 6.5
into the folder:
3. Make sure that the version of Nisus Writer Classic you use has exactly the same name as the "for…" of the application you use. If it has a different name, e.g. "Nisus® Writer 5.0.2", just rename it.
3a. (For the more technically savvy… alternatively you can change it in 'DropOpenWithNW*.app/Contents/Resources/script'. If you try to do so, make sure that the encoding of your text editor is set to UTF-8 with no BOM and End of Line code to LF (Unix).)
DropOpenWithNW*.app is a very simple shell script wrapper, of which the only function is to redirect a file to be opened by it to Nisus Writer Classic.
4. Remove "/Library/Caches/com.apple.LaunchServices-01450*.csstore" (014501 if you are the first admin user).
5. Restart your Macintosh.
6. Nisus Writer Classic documents will now be associated with DropOpenWithNW*.app as the latter supports the same file type as Nisus Writer Classic. And the original icon will be restored because DropOpenWithNW*.app does not have any document file icon.
6a. If that is not automatically done, select a Nisus Writer Classic document in Finder.
6b. Choose Get Info from the File menu.
6c. In the Open with portion of the Info window choose DropOpenWithNW*.app from the pop-up menu.
6d. Click Change All.
6e. In the alert that appears, click Continue.
We do not know the cause and the nature of this bug. We have reported it to Apple, but have not had a response.