Since updating ClarisWorks from version 4.0v4 to 4.0v5 (quite some time ago), I have had the same problem on two different Macs. Recently, reader Alan Mitchell reported a similar problem. Essentially, I am unable to import (or export) certain types of documents, most especially plain text (TEXT) files. When I first tried to import a text file after updating, I got a message that said "The file 'Text' couldn't be found." This happened both on my PowerBook 3400 and my Power Mac 7500. To try to fix this, I deleted the XTND Translator List Preferences file. This eliminated the error message but still did not allow the file to open. Now ClarisWorks does nothing at all following this import request. No message appears; no document opens. Oddly, some text documents do open normally. I cannot determine why some do and some do not.
Update: Several readers have already replied to this. A few suggested that completely reinstalling ClarisWorks should fix this. Brent Ito says that actually all you have to to is delete the Claris Translators folder (in the Claris folder) and do a custom reinstall just of this folder. Other readers have offered still other suggestions. I will sort through this and see what works. Stay tuned.