and here's a patch for the start button

--- card.pl        2004-10-02 20:15:10.000000000 -0300
+++ fixed.pl       2004-10-02 20:14:51.000000000 -0300
@@ -7,6 +7,7 @@
 use constant COS => cos(3.14159265/18);
 
 my $color = 'darkolivegreen';
+my $rotating;
 my $score = 0;
 my @delay = (30,
             20,
@@ -68,6 +69,8 @@
           -height => 2,
           -padx   => 10,
           -command => sub {
+                  if (! $rotating) {
+                          $rotating = 1;
             $c->itemconfigure($_, -state => 'hidden') for $arrow, $ms
+g;
 
             for (1 .. 10) {
@@ -76,8 +79,11 @@
               push @s => splice @ids, int(rand @ids), 1 for 1 .. 2;
               rotate(@s, $delay[$score]);
             }
+            $rotating = 0;
             $topText = "Click on the correct box.";
             $selFlag = 1;
+                  }
+                  
           })->pack(qw/-side right/);
 
 MainLoop;
[download]