Strange behaviour of QTreeView::moveCursor():
1. If right arrow pressed moveCursor() returns wrong model index.
Possible reason:
QModelIndex next = current.sibling(current.row(), visualColumn);
need to be replaced by
QModelIndex next = current.sibling(current.row(), d->header->logicalIndex(visualColumn));

2. After editor closed tree view starts editing of same index.
Possible reason: QTreeViewPrivate::isItemHiddenOrDisabled(int i) in QTreeViewPrivate::below(int item) called by QTreeView::moveCursor() use isIndexEnabled(viewItems.at.index) and viewItems.at.index has always 0 in it column. In my case this column is fully disabled.