I upgraded a dnn 6.xx to 7.2.1 a few weeks ago. I have seen been struggling to figure out what could be causing the modules to revert to their original position after I refresh the page.
Originally it was on an iis6 server but i had it moved to an iis7.5 server when I did the upgrade. 

I tried changing the admin panel from the default to the ribbon and then to icon. That did not help. 

Are there any other suggestions that I may be able to explore?