So I have a simple tree (grid type) with two columns. If I Tab on the last column in this 'grid' I see the following unhandled exception thrown by the tree control (at least I cannot catch it in my try{} block). Tree TabNavigation = Next Cell. Is this a known issue with UltraWinTree v9.2.20092.2042? It seems the mere fact that there is no next cell causes the crash...
I took a look at our code and at a glance it would appear that this should only happen when the ActiveNode is null, and that should only happen when there are no nodes, and when there are no nodes, no cell navigation should be possible. Usually when there are seemingly contradictory conditions necessary to reproduce the bug, the control is in some very unexpected state, but without more details it is difficult to speculate about what might be causing it. This is almost certainly a bug in the control (by virtue of the fact that we are internally causing an unhandled exception), so you might want to report it as such.