We'd like to input "0:zero" in the cell of Time Entries.
Because if we don't work on that day, we'd like to input "0" naturally.
I think it's very natural interface. The many users of our project hope so.
We don't want to push "Delete" button, or "Delete" Key.
Thank you.BR.
Ideas Administrator

Our time entry includes TYPE which can be extended to cover other types of non work. If not applying your time to a project you should apply your time to a different type to record the entries you did spend your time doing.