[plt-scheme] DrScheme Debug button

Gregory Cooper wrote:
> When you click the Debug button, you should see a small green arrow 
> indicating the current expression.  Does this happen?  (It may take a 
> while.)  You should also get a toolbar with Pause, Continue, and Step 
> buttons.

No. When I click the Debug button (with a simple function definition and 
some expressions using it in the Definitions window), I get the toolbar, 
but Continue and Step are greyed out, and Pause seems to have no effect 
when I click it. It evaluates the expressions in the window as if I had 
pressed Run, and then gives me a prompt in the Interactions window. 
There is no green arrow visible anywhere. --PR