To record an entry with no start/stop time, navigate to the timer detail screen (by tapping the cell of any timer from the home screen), then select the '+ Entry' button for the timer you want to create an entry for.
From the entry detail modal, simply input the desired duration and click save. While this entry won't appear on your timeline (because it doesn't have a start/stop time) it will be accounted for in the total that shows on your ring graph, reporting, and the timer detail screen.
Watch a video about the ways you can track time with Hours TimeLord here: https://youtu.be/xRIhInoDl9Y