I am a newbie, was working in formulas, and made the mistake of right clicking on a formula button and then selecting ALLOW DOCKING. This apparently had the effect of removing the screen divider between the top half of the screen and the bottom half (where you build the formula. In fact, it seemed to reverse them and I cannot get the screen divider back. I have tried rebooting, and anything else I could think of to restore the formula screen defaults.