Thank you for all of your replies.
Now, to answer some of the questions...
I forgot the name of the yellow tube (I'll ask the guys who ordered it if I remember), but we did not use the slide connectors. We used soldering guns instead to melt it down and connect it!
Yes, we have two shooters and they are parallel to each other. The gates open/close for each shooter so that we can choose which shooter to shoot with(even both if you are running out of time). The aim is up to the driver since we packed away our camera in week 4 or so. There is a video of it shooting using both shooters(when we only mounted the shooters on the robot) on our website.
Click here.
I hope that I answered every question (I know that I didn't answer what exactly the yellow tube's name is). Good luck, everyone!