I just upgraded to the latest version of Moster Widget and I'm getting undefined index warnings on all stock widgets, and none of them are showing up. See screenshot.
http://dl.dropbox.com/u/curtis.mchale@gmail.com/Screen%20Shot%202013-01-07%20at%209.52.46%20AM.png
http://wordpress.org/extend/plugins/monster-widget/
Could you please be more specific? I getting a 404 on that Dropbox link :( Which index? Which array?
Hrm, not sure why those links are giving 404 errors. Link below again, it looks to me like it is on all widgets (though not all notices are in the image).
https://dl.dropbox.com/u/73804/Screen%20Shot%202013-01-07%20at%209.52.46%20AM.png
That link worked, thanks! I am unable to reproduce this in a standalone version of trunk with Twenty Twelve and no active plugins. Is it possible that a plugin or theme code is causing this issue? Have you removed core widgets? If so, please post the code that you are using.
I am using a theme from AppThemes, and the code is of less then stellar quality.
Once I get the theme out for the client I'll back track and see where the conflict is.