Also, If I reset the origin of this 3ds within Blender and then import the object into Unity, I seem to be able to move the pivot with gamedraw, but then if I detach a sail from the boat model, using gamedraw, I have the same problem moving the pivot for that newly created sail object.

EDIT: After detaching the sail from the boat, gamedraw put the object at the root in the hierarchy and I had immediately placed it as a child of the boat.  So when I edited the pivot point as a child of the boat, that was what caused the pivot point adjustment to go crazy in this case. I still think it's funky the way it works, but  at least I can work with it now.

Sure, I just imported this free Sailboat and tried to set the pivot point on it. Thanks for your help.

I had read that and did make sure that I was set at pivot/global before even clicking on the gamedraw icon.  I can move the pivot along the x axis but when I try another, the object wobbles as I move it and then it just flies out of view and I have to undo.