Already posted
It will be possible that you can choose more than one toplist to vote in this system. And you can decide how much coins the user will get for each toplist.
Can you explain what exactly a referal system is? I dont know ^^
The referral system is a link that every user have, example: metin2example.com/ref=andres and when the user registers using that referral link the referral in this case "andres" gets a new referral, you can add coins per referral or things like that