usermanager with hotspot firewalling

Hello,

I have set up my usermanager successfully and it works very well with the hotspot. I also enabled DHCP server where people could easily see my hotspot page. The problem i am having is that how can rechargecodes or customised username and passwords be bound to an IP and MAC address so that it can only be used strictly by that IP and MAC address?

I noticed that such rechargecodes or usernames and passwords could easily be copied from clients and used in other computers thereby creating problems.

Secondly, Usermanager does not have time of day billing such that u can only have access to the internet at certain time of day until the following day. Is this a limitation which will be corrected?

Love to all