Can you explain the process that you're using to resize and scale your content?
Which Anchor option did you use?
If you're resizing in order to export HD video, you could just set the render size in the video export dialog.
If the stage resizing continues to fail, you could copy the layers and paste them into a movieclip, then put the movieclip on the stage, and set it to 200% (after changing the stage size without scaling content).
Modify > Document
Then changing the stage size and selecting 'scale content to stage'
If you don't choose an Anchor option your resizing should work as expected. If that isn't successful then try Colin's solution of resizing a movieClip.