The Johan
It's possible but you'll most likely have to disable a security setting. By default Access Server uses TLS auth security, but it seems like the Mikrotik router does not support this. You'll have to add 'auth none' to the server directives override in Access Server, and you'll have to download an autologin profile for a user account that has that privileges and copy/paste the keys out of there and save them as separate files and then load them into the Mikrotik router.
Good luck.