While I am in Continuous view (really large schedule!) how do I add a vertical link?
You should be able to do this. When in Continuous View, there should not be more than one page. If the end of the vertical connection is a milestone off of the screen (in the future), use Shift+PageDown to get to it, instead of clicking the forward-scrolling arrow.
Remember the steps to place a vertical connector:
(all of these clicks are single clicks)
Click the Plus tool in the ToolBox
Click the symbol (on the schedule) from which the connector will come
Click a vertical connector in the ToolBox
Click the symbol (on the schedule) to which the connector will go
The vertical connector should then appear.