Thank you for your post.
I am unable to replicate the problem with several files running under Windows XP SP3 (and also Mac OS X 10.7.3). I will try later with a Windows 7 (64-bit) machine when I have access to one. I'll keep you posted.
Well, seem to have banished problem:
Extended layout and Selected All.
Dragged everything down layout, which revealed a white area at top.
Pushed everything back up layout and Hey Presto,
Graphic Ruler in agreement!
All layouts seem ok.
No idea why, but ho hum!
It doesn't appear to be a Windows 7 issue, and since I'm unable to replicate the issue, can you send me a clone of one the files? Check your Inbox at the top of this page for instructions where to send the file.