Adding your own private comments / notes to a Chessable MoveTrainer® course is possible. First, open up the line you want to add a comment to in its own page by clicking on its name/title.
Then, in the newly opened page (opens in a new tab), scroll down to the comments area, and tick the private comment checkbox and simply write and post your comment. These comments will be only visible to you.
We are also working on the ability to display any comments you post here directly into MoveTrainer®.