Gate is an action that you can use in your kismet sequence. If you want to make sure that a particular event that you've set up doesn't trigger until you've done something else, you can set up a Gate action that you can set to let events through or not. The Gate action would sit between the Touch event and whatever actions you have that trigger from the Touch event.
Separately, you should know that staticmeshes and interpactors are 2 different things. An interpactor may use a staticmesh base, but cannot be called a staticmesh, because it is a dynamic actor.