It's been many years but, yes my Buc board used to have to be secured in the down position or is would float up. A short line ran from the upper corner to a cleat or jammer on the trunk. Release the line and the board would pivot up. I have no idea if it was a custom or stock board. That was before this web stuff when getting info was a bit harder.
For trailering I recall looping a bungee or rubber cord over the raised board and forward thru the ports and beneath the mast step. This kept the end of the board above the hull bottom so it wouldn't catch on the trailer.