I don't know if this helps but, I noticed the same thing. Then, I discovered that there's a separate data display panel for each item in the Collections navigation panel on the left side of the window. I had to arrange the columns for each one and they stuck. In my case, it was only three panels I had to arrange - My Collection, United States, and General Issue. Now when I exit and then later restart StampManage, the columns are set to my preference.