savegame compatibility is not assured, you should always finish your current game before updating.
Important : delete previous version of the mod, else the VFS may cause bugs. See newunits.xls or forum thread on civfanatics website for details Diversity : hundreds of new unit models for diversity, no gameplay change. Existing formations have been reworked to reflect the change in scale, and new (14) formations have been added. Formation : most units are now multiple figure, and the number of figures is raised in all human and mounted units. The sea and air units are respectivly better proportionned.
Rescaling : all human and mounted units have been scaled down, no more giant infantry against tank ! Of course, the relative scale is nothing close to realism, but it looks way better IMO. Regiment and Ethnic Diversity for Civilization V.