There is a difference between the fonts which are installed with ClarisImpact 1.0v3 or earlier, and those which are installed with ClarisImpact 1.0v4.
If you have previously installed ClarisImpact 1.0v3, and update the application to 1.0v4 (via updater or through a custom installation), but do not update the fonts which are installed, your documents will use the 1.0v3 font information without any problem. When you open and save the files, using the 1.0v3 font information, in ClarisImpact 1.0v4, the files are assigned to those fonts.
However, if you then replace the ClarisImpact 1.0v3 fonts with the newer ClarisImpact 1.0v4 fonts, the files do not convert the font information to the new fonts. Basically, the document will continue to try to address the old font information.
What will happen on your machine? ClarisImpact will react as though you have a font in your document that is not currently installed in your system. You will see a "Font not Installed in System" alert when you open your old documents, and the fonts in those documents will display and print in Geneva.
Fortunately, there is an easy workaround. Open and save the files in 1.0v3, and then open them in 1.0v4. The font conversion will then work properly. Note that any new files that were created in 1.0v4 with the 1.0v4 fonts would work perfectly.