For starters, the new game is not browser based. If he is using browsers for the game he is trying to load the flash based game. Does he have flash on his computer?. If win10 probably not. With few exceptions newer browsers don't even let flash run anymore,(hell for that matter I believe with microsoft, they won't let it or about to not let it run on win10) without you, the operator, jumping through hoops to get flash to run. And then prepare to do it all over again everytime you reopen the game. Is that the crash you are referring to? In other words, it is loading, but just not running.
Search the forums and you will find the download link to the PCEA(that is the new version for PC's) download that and run it and then you will have the new game you stated in the topic. PCEA= Personal Computer Early Access(this is supposed to be a work in progress beta of what will end of being the game. It looks identical to the mobile version for a phone or tablet that doesn't actually run windows. Don't have and have no need for anything Apple, so can't answer for those OS's.