In the director's guide we suggest that you put the tri-board on 6 foot tables. I find that 6 foot tables works ok for me. However, if the facility should have 8 or 10 foot tables, it would be better to use them. Generally, what happens is a participant will spontaneously hold the panel while they insert the pegs if it starts to move on them. I just ran POL with Alan Meeker from Advantage Performance Group and he assigns someone from each group to hold the outside edge of the panel. He also asked the hotel for 3 foot round cocktail tables to put under each wing of the panel. You may want to use one or both of these approaches if you are worried about the stability of the tri-board.
Also, if you pull the cable ties tight, it may not allow you to position the boards the way you want. So if you want to tighten the ties to get more stability, tighten them after you have them in position. You may have to cut the ties to put the tri-board back in the box. There are extra ones provided, but please let us know if you need replacements.
Thanks
Garry