Aperture adjusting master file??

Hi I have updated to the latest aperture and am spotting a pretty serious problem.

If I choose to edit in another app (Photoshop) after I save in photoshop two things occur:

The original file is updated

The preview does not update.

Previously when editing with another app, a version would be created preserving the original, which is how I prefered it. I even outputted the master file and that has been adjusted.

This is a concern for me.