Basically create an extension for GameMaker Engine which will allow us to display Chartboost ads (all formats). Should work on both Android and iPhone.
Another user tried to create one for Android with the old Chartboost sdk: [url removed, login to view]
The basics are expected, like show interstitial and video ads. Also all the buttons should work, back, pause, etc. Finally need a function that will tell if ad was shown or not.
Also the show more apps function should work.
FYI the link in the original post has a working demo for an older Chartboost sdk for Android. That needs to be updated and made working for the current version and add iOS support.