If all else fails...try again...
The solution is the use of the "EDIT" key <F2>.
After clicking on the range name, and then clicking in the "Refers to" box, hit <F2>.
You will then be able to use:
<End> to get to the far right,
<Home> to get back to the far left,
<Control> <Right-Arrow> to move right in a "Tab" way,
<Control> <Left-Arrow> to move left in a "Tab" way.
Hope this is what you were looking for.
Regards, ...Dale Watson dwatson@bsi.gov.mb.ca