Dedicated IP and Domain Mapping Plugin

Hello, I am slightly confused over this plugin; just want to make sure of a couple of things:

1. Dedicated IP. I have a dedicated ip address, but it does host sites other than wordpress sites. I have set up multiuser for, and it's working great. But I'd like to map to content for instance.

1a. I am waiting on my host to add to the DNS zone so I can have the A record point to

2. For this plugin to work, does it need to be on a dedicated IP address WITHOUT other standard PHP websites on it, or can it run at my main address?

Thank you,