According to tst answers (not a color problem ;)), it seems that I'm not the only one to have misundestood your question!
It is not possible to write in the upper left corner of a table. A workaround would be to overlay a string above this part of the table. I have posted a few days ago a similar solution, to position a boolean over a table. See here :
http://forums.ni.com/ni/board/message?board.id=170&message.id=101841#M101841
Hope this helps !
CC
Chilly Charly (aka CC)