Hi,
I didn't find the topic on the forum related to this issue but I wanted to let you know that I had the same issue and solved it by setting Manager+ permission on Today in "Access data (project dependant)". "Manager" added the right to create items, and "Manager+" to delete items.
Surprisingly, it didn't work for one profile (the user logged off, and logged in again) after setting "Manager+" so I had to put "No access" on this profile and then "Manager+" again, and it worked.
I didn't find the topic on the forum related to this issue but I wanted to let you know that I had the same issue and solved it by setting Manager+ permission on Today in "Access data (project dependant)". "Manager" added the right to create items, and "Manager+" to delete items.
Surprisingly, it didn't work for one profile (the user logged off, and logged in again) after setting "Manager+" so I had to put "No access" on this profile and then "Manager+" again, and it worked.