PAF 5 seems to have major errors in its graphic file linking in RTF "Print to File" exports. This could cause memory problems. Also make sure that the Word SR-1 Service Release has been downloaded and installed, and that your virus software is up to date.
The Word97 Normal.dot template may be corrupted. In Windows Explorer, delete the Word97 Normal.dot template. Word will create a new one on next bootup.
Short answer: PAF 5 RTF exports may not be ready for prime time, and macro viruses are abundant. In the case of PAF 5 it may be difficult to tell which is which.