Can't run my app with older version of jre anymore. Help!

Question

Java Web Start is supposed to allow applications to use older versions of Java JRE. My applet uses 1.6.0_31 because it doesn't work with 1.7. (Backward compatibility? Don't ask.)
When I first set it up a couple of weeks ago, it worked. Now, with JRE 1.7 officially released it does not. When I try to run it, I get the following message:
"This application would like to use an older version of Java (1.6.0_31) that is not installed on your system. We recommend running the application with the latest version o java on your computer. Then there are two buttons.
One button says "Run with latest version". The other button says "Cancel". When I click on "Cancel" the application fails with the following
basic: LaunchDesc location: http://relativitysimulation.com/Applet.jnlp
network: Created version ID: 1.6.0.31
network: Created version ID: 1.7.0.03
network: Created version ID: 1.7.0.03
network: Created version ID: 1.7.0.03
network: Created version ID: 1.7
network: Created version ID: 1.6.0.31
network: Created version ID: 1.6
network: Created version ID: 1.7.0.03
network: Created version ID: 1.7
network: Created version ID: 1.7.0.03
network: Created version ID: 1.7
network: Created version ID: 1.6.0.31
network: Created version ID: 1.7.0.03
network: Created version ID: 1.7.0.03
network: Created version ID: 1.7.0.03
network: Created version ID: 1.7
java.util.MissingResourceException: Can't find resource for bundle sun.applet.resources.MsgAppletViewer, key appletpanel.ExitException[ 0]
     at java.util.ResourceBundle.getObject(ResourceBundle.java:393)
     at java.util.ResourceBundle.getString(ResourceBundle.java:353)
     at sun.plugin2.applet.Applet2MessageHandler.getMessage(Unknown Source)
     at sun.plugin2.applet.Plugin2Manager.logAppletStatus(Unknown Source)
     at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
     at java.lang.Thread.run(Thread.java:722)
basic: ExitException[ 0]
ExitException[ 0]
     at com.sun.javaws.ui.SecureStaticVersioning.showCannotDownloadDialog(Unknown Source)
     at com.sun.javaws.ui.SecureStaticVersioning.canAutoDownload(Unknown Source)
     at sun.plugin2.applet.JNLP2Manager$JnlpLaunchState.doJvmSelection(Unknown Source)
     at sun.plugin2.applet.JNLP2Manager.prepareLaunchFile(Unknown Source)
     at sun.plugin2.applet.JNLP2Manager.loadJarFiles(Unknown Source)
     at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
     at java.lang.Thread.run(Thread.java:722)
security: Accessing keys and certificate in Mozilla user profile: null
security: Reset deny session certificate store
Looks to me like Cancel does not mean "Run Older Version". While I am debugging why I can't use the latest version of jre, can someone please tell me how to use the older version?
Edited by: 932841 on May 8, 2012 8:54 AM - corrected typo

Answer 1

I'm the developer. And thank you for your prompt response. I have been given a work around so that the applet can use version 1.7. But that still doesn't explain what I am doing that makes Java fail to use the older version.
I put this code in my jnlp file on March 27th when I realized that my app didn't work with version 1.7. I tested it at that time and it worked. In the process I installed and uninstalled java 1.6.0_31 ( and 1.7) several times. Maybe something important got corrupted then.
<resources>
     <j2se version="1.6.0_31" href="http://java.sun.com/products/autodl/j2se"/>
Added this -----
Oh, if someone else wants to try this app on their machine, feel free. It is at
http://www.relativitysimulation.com/Applet.html
Edited by: 932841 on May 8, 2012 11:13 AM