The Maple Math button is not working for me in the MaplePrimes editor.  No matter what I enter as Maple Expression, I get You have entered an invalid Maple expression, no preview, and nothing is inserted.  The same goes for the Maple Plot button. 

I'm using Firefox 58.0.1 under Windows 10 (64 bit), but this also occurs with Internet Explorer.

I want to have a Plot component display animations, controlled by a button. I want each click
of the button to show a new animation.

So e.g. the Action when Clicked for the button might be something like this (for animations alternately in blue and red):

use DocumentTools, plots in

if cc = red then cc:= blue else cc:= red fi;
Do(%Plot0 =animate(plot,[sin(x+t),t=0..Pi,colour=cc],x=0..Pi,frames=4));
SetProperty(Plot0,play,true,refresh=true)

The following file contains a student's midterm exam answers (with name and student number x'd out). When I try to load it, I get "There were problems during the loading process. Your worksheet may be incomplete", and only a small part of the file appears. Using text editors, I can see that there is much more to the file. Is there any way to recover this exam?