My Gnucash has changed - making changes

[David Ryder]

   Ubuntu 12.04
   I opened Gnucash yesterday - things had changed. I installed 2.4.11
   some time ago (over a year?) but now it is saying it is 2.6
   However all my columns sizes had changed - but the most annoying thing
   is the pop up box every time I change the reconciled from 'n' to 'c'
   asking me if I want to make the change. The options are 'Remember the
   answer and don't ask me again' and 'Remember the answer for this
   session'. Seems silly to me for the reconciliation column when changing
   'n' to 'c' but sensible if changing 'y' to 'n'...
   I _do_ want to be asked if I change a 'y' to a 'n' in the reconciled
   column - so I can't choose 'don't ask me again'.
   But I _don't_ want asking if I, say, change 'n' to 'c' or add a
   reference in the Description or Num columns.
   It was all working fine last week.
   Can anybody tell me if this popup is per column or universal to any
   changes?
    As I had obviously got this working the way I wanted it some time ago
   I'm hesitant because Gnucash has apparently updated itself (I didn't
   know it did).
   Many thanks
   David