In the attached test case, the field shown as "Panel" is a variable called
"Reader" that is used to control the output of the two conditional text fields
that occur later in the document. I've found two problems with this: 

1). When I first wrote the document it worked as long as the variable was
visible, but when I marked it as invisible it behaved as if its value had
changed to something other than "Panel". If I made it visible again it seemed to
regain its value of "Panel". In other words, as long as it was visible it worked
properly, but when it was invisible it never acted as if it contained the value
of "Panel".

2). I saved the document as it stood and closed OO, but when I re-opened it I
find that I can no longer make it invisible.  I can change its value and the
condional text is processed properly, but no matter what I do I can't make it
invisible any more.