1) There is a Windows message to set the tooltip timing – TTM_SETDELAYTIME. This would let you keep the tooltip open longer. For example, at the end of ToolTipControl New you could add:
.SendMessage(TTM.SETDELAYTIME, TTDT.AUTOPOP, 30000) // 30 sec
Note: I have not tested this.
2) I am not sure what you mean by “false is returned”. Do you mean the value passed to ItemClicked? This value is the row currently selected. If no row is selected it will be false.
According to the MSDN documentation for list view NM_CLICK you must use LVM_SUBITEMHITTEST (ListViewControl SubItemHitTest) to determine which item was clicked on.