I have a template that I made 1 year ago that keeps getting updated and now is on update 34
In this template I have everything I need for after the actual game is created:
Leaderboard (autologin, function for auto submit score),
IAP to remove ads,
Ads
Sound and music controll
Share to Facebook and Twitter
All sorts of elastic movements for UI panels and buttons
HiScore that will autosave and autoload from LocalStorage
I usually start from this template and make my game on top of that and delete things don't need (like Leaderboards or IAP)
Or If I need only let's say the audio events I first drag and drop the sprites/objects from the template to my projects then the additional events.
Is a little difficult to copy/paste in C2, but this is life in general:)