How do I manually add and remove beats using the HRV module?

When using the Heart Rate Variability (HRV) module add-on for LabChart, it is possible to manually add and remove wrongly assigned beats to the analysis.
To Remove a Beat Marker:
Select the area around the beat marker of the beat you wish to remove by holding down the left mouse button and dragging the area.
You can then select 'Delete Beat Marker' from the HRV menu and the beat marker will be removed and the intervals recalculated accordingly. NB this option will be greyed out if a selection is not made.
To Add a Beat Marker:
Make a single point insertion on the LabChart trace on the R wave that you wish to add.
You can then select the 'Add Beat Marker' option from the HRV menu and again the r-r intervals will be recalculated.