The different modes for keeping drawings visible for multiple frames
There is a mode to display drawings until the next one appears. You will find the menu in the player (the 'H' Symbol) and it works like this:
Held Mode - Add to Sketch
Anything you draw will be held on subsequent frames.If you draw on subsequent frames the strokes will be added to the active drawing.
Held Mode - New Sketch
Anything you draw will be held on subsequent frames.If you draw on subsequent frames, it will automatically spawn a new image annotation, the strokes will be added to this new image.
Disable Held Mode
Anything you draw is only visible on the frame you drew it on