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Both versions are included in archive, but only "Basic Version" is activated by default.
Activate "Widget Version" via ByREV Category Cloud from wp admin menu:
Note: Widget Version version does not work without the "Basic Version" so, both version must be active ... otherwise you will receive an error message:
Ups! ByREV Fast Category Cloud Plugin Error!
Widget Version does not work without Base Version, so please enable it and the Base Version!
If you get "division by zero" error, enter in admin/widget config and save config via "ByREV Category Cloud"