Supporter + Domain mapping Option Not Available???

Hi, WPMUDEV team,

I tried my best to avoid asking any unnecessary questions, but now i am stumped. Well i have 2 questions:

1: Where i is the option to allow domain mapping as a supporter upgrade? I Have domain mapping Version 0.5.4.1 and supporter Version 2.2.8.

Screenshot of the option here: https://premium.wpmudev.org/wp-content/uploads/2010/09/domainmapping.jpg

I am on hosgator shared business plan which comes with a free dedicated ip and ssl. After following the installation instruction for DM plugin i checked my ip address in FF browser and it leads me to hosgator 404 error page.

So my question is how to fix this ip issue?

Thanks

Follow up Q: My main blog domain is mydomain.com i purchased mydomain.net for mapping purposes, but when i go to the .net it still takes me to the sub.domain.com even though the address is mydomain.net and i pointed the .net to the .com root folder.

So is that normal? should the .net take me to the .com and the other way around?