Migrating existing STATS files
There are considerable indexing improvements in the Statistics facility for Version 6 to allowing for the extended search capabilities by NODE.
Due to this, it is recommend that when migrating to Version 6 that you preserve your previous stats files by performing an archive on the previous version of Connect:Direct. Then perform a Stats Cold start using STAT.INIT=COLD command with the new version of Connect:Direct.
The same recommendation applies when backing out or migrating back to the previous release, archive the data and then Cold start.