When upgrading Domino or troubleshooting design issues, keep in mind that most Domino templates do not have their replica id changed from release to release. Two prominent exceptions are the Mail template (which also has its file name changed from major release to major release) and the Bookmark template. For the rest, the expected behavior is that any updated design elements will overwrite the template design element on a down level server. For example, when changes are made to events4.ntf (either for a new feature or bug fix) in 8.5.3, those changes will propagate to 8.5.2, 8.5.1 ... 7.x ... 6.x, etc. These templates are designed in such a way that their overwriting of the down level element should not adversely affect the behavior of databases that inherit the template's design. Each time an element is modified and saved, its sequence number is incremented. The sequence number is then used to determine whether or not a design element in the source .NTF should update the element with the corresponding UNID in the target .NTF. Standard replication takes care of making sure that all templates in the environment have the most up to date design. The Design task then takes care of updating the .NSF files that inherit the template designs.