You're telling Construct to activate the group named "Double Jump," but you have no group named Double Jump. It's just some regular events that aren't in a group. To add a group, do like so:
<img src="http://i30.tinypic.com/2qiv1bt.png">
Enter the name for your group. And since you want your group to be disabled by default, be sure to check the box:
<img src="http://i31.tinypic.com/2yzais1.png">
Now that your group is made, drag all the events that you want in your group into the group:
<img src="http://i29.tinypic.com/sbk8yg.png">
Also, the default value for your global "doublejump" variable is 1. That's not going to work. You want the group to activate when it becomes 1... so if it starts at 1 then you're going to activate your group right off the bat. You need to change this to 0:
<img src="http://i28.tinypic.com/315fvwi.png">
And after all that it will work fine.