Hi,
we have no problem with activation via "Load planing data" button in cdm_viewer. Maybe you do not maintain fields "Activity: and "End of Usage" in excel? Here my file example:
Location;Product;Activity Status;End of Usage;End of Use TZO;Flag Safety Factor;Safety Factor;Change User;Edit;Edit Granularity;Day;Granularity;Quantity;UoM
R204;0000000000000000000000000000000000361600;X;20501231;UTC;X;1;LTMG00000341;W;W;201420;W;12;