Very interesting bug in Qt in which I will debug. For now, and since we need to release with the source version of Qt (not patched) we need this workaround. The problem
is that when you select by dragging with a rect a set of items, say (1, 2, 3) and you Ctrl+drag another set (5,6) the (1,2,3) selection is lost. If you do the same, that
is: select (1, 2, 3), now Ctrl+click on (4), it is not lost. Now, ctrl+drag another set (5, 6), the selection lost is (4). So we can say that the selection lost is the
last one done.
This is only a workaround and should be removed when fixed on Qt (I am going to debug it on Qt, to see where the fail is).
This workaround does not only fix KCategorizedView, but QListView also.