first of all it's a great plugin but you have a lot of issues if you want to create a text/html box. Boxes doesn't work like they do in WordPress pages.
1. I don't know why but in text mode each box as page creates
<strong> commands with each mouse click.
2. If I want to link a word the WP Popup does not appear.
3. New line or linefeed doesn't work in WP standard mode. All text is shown in one block.
Please can you check these issues? See my sample page here http://www.socialmedialernen.com/toolpage/socialmediaschule
After each box safe it's better to stay in edit box mode. It's a hard that I've to jump each time back to edit mode.