Try the webstart if the applet is misbehaving. Drag and drop some of the following parameters (a single line at a time) onto the left pane of the interface:

seed:305;#sides:10;smooth:80;%smooth:50;opaque:1;line:5;convex:30
seed:309;#sides:16;smooth:50;%smooth:100;opaque:1;line:12;convex:20
seed:10107;#sides:12;smooth:100;%smooth:100;opaque:0;line:5;convex:40