When you are building the APK, what have you put in the input field at the top of the dialog?
Can I also suggest that you should also change the "myname" bit to something personal to you.
https://groups.google.com/d/msg/androidscript/80Fhj1fq_Tc/rbSzChylDwAJ
When you build your apk, do you get a dialog asking for your details?
Do you get a warning message to backup the keystore file?
What is displayed if you run this line of code in a temporary app in the IDE?
alert(app.GetFileSize( "/sdcard/.DroidScript/debug.keystore" ));