In the activation field of the waypoint put
end1=true
In the condition field of your End#1 trigger put
end1
So when the WP is completed the variable is set to true, the trigger fires and the mission ends. However, it is not good practice to have things in your mission dependent on player waypoints - people will play the mission in ways you, the designer, can't even imagine, so there is too high a possibility of the end not happening. The player may have missed a waypoint way back, for instance. Much better to have everything triggered by, well, triggers.
You can make the trigger go off if a certain unit is present. Create the trigger and the unit, then WHILE IN GROUPS MODE link the two and you get special options in the activation field.
Hope that does the trick.