Download the Java applet class file to your desktop.  Record the applet parameters for height and width.  If there are additional  parameters the directions that follow may have to be modified.  For this example the

Place your cursor in the position you wish the applet to appear.  Select "Java Applet" from the "Create" menu.

Click on the folder to the right of "Base class name", then navigate to the appropriate class file:

After clicking "OK", select "Locate" on the popup screen that remains. Use the "Add/Replace File(s)" button, to navigate to and add all of the remaining class files required to operate the applet.

To change the width and height parameters in Lotus Notes 5.0, place your cursor immediately to the right of the applet you inserted.  Click the backspace button once.  If the properties screen does not pop up, choose "Java Applet Properties" from the "Java Applet" menu.

Change to the appropriate height and width parameters on the "Java Applet Properties" screen.