I’ve had the same problem.
I found out that you can enable the auto paragraphs in the gcb.class.php.
If you search the class on ‘wpautop’ you’ll find that this is set to ‘true’. If you change this to ‘false’ the <p> tags will be automaticly inserted in a contentblock with type ‘general’ while editing in visual mode.
Keep in mind that this will also happen if you use other types like HTML or PHP. So use txt view for these types
