In CS2, I could copy a grouping, and it would stay the same when pasted. In CS5.5 and CS6, it changes after I paste it. Is there a setting I need to change?
You'll have to do much better as far as detail goes. I have no idea what "it changes" means.
As an example, the table column widths changed and I had to resize everything.
Within the same file or into a new file? Screenshots would help.
New file, but both Indesign.