Drawing points don't snap to OHLC values correctly

If you want drawing points to snap to OHLC values of bars automatically, then you need to enable Magnet Mode on the left-hand side of your chart (the icon should turn blue when enabled). 

Magnet sensitivity can be adjusted through the magnet mode menu:

Strong Magnet pulls the drawing points to chart values (bars), regardless of the distance between the points and chart values.

Weak Magnet pulls the drawing points to chart values (bars) when you are drawing near them.