I also did not find that in "search" or other forums
I have the textarea that contains the code and press save application.
Then the textarea comes back and has the changed data in it but below there is red text and it says:
Object reference not set to an instance of an object.
Below the two buttons "save application source" and "run Caja Tester"
When I click on forums for example and go back to edit my app, the code in the textareaagain shows the old value.
I uninstalled / reinstalled my app. The error is gone but now I can no longer test it on my page because there is no option to "install app on your profile" - I have a music account. I will have to wait until myspace moves to apps in music accounts.....