Without seeing your entire configuration I could not say. Submit a ticket with KH support and they should be able to help you out. Webmin is not a full featured control panel so there might be a lot of manual configuration via shell or otherwise that you would have to do.
Not sure but I think you are looking for some tutorial for setting up apache no ? replied to your pm, I'm on MSN if you need help because on a VPS thats not like a normal shared hosting, you have all configurations to manage yourself, so I'd suggest you to read the online docs at httpd.apache.org and each other apps you want to setup.