PlanAhead and Vivado tools support Unicode characters in the project path. However, Project Navigator and ISE Design Suite tools only support Alpha-numeric ASCII characters and a small subset of notation characters such as the underscore.
As such, any IP that relies on CORE Generator (Non-native IP) cannot be generated in or added to a PlanAhead or Vivado project if Unicode characters are in the path to the IP.
Native IP (using new XSpice GUI) can be created and stored in a directory with Unicode characters and added to a project with a name containing Unicode characters.
Note: No new IP are being developed as non-native IP. This issue will become obsolete over time, but users should avoid paths with Unicode characters when adding legacy IP cores or importing legacy designs from ISE Design Suite.