Yes it’s perfect for a T4 :) The rectangular shape of the DubPod really maximises the space available & being a single centre pole & simple door frame configuration it’s easy & quick to put up. One of our recent customers put it up in 15 mins on the 2nd pitch!

Here is a link to our video

In terms of connection there are generally two options using your gutter rail at the top of the van:
Option One
You can use a universal pole and clamp set which can be bought from most retailers of campervan accessories.  Just Kampers have this product -
Awning Pole and Clamp Set
This fits by simply sliding the pole through the canvas pocket on the underside of the Dubpod connector next to the awning bead. The pole is then simply clamped to the vehicle using the clamps in the kit.
We find this is the most secure fitting when the weather is windy.
Option 2
Using a figure of eight connected to the gutter rail, We have found the Kampa brand drive away kit to be a good solution
You slide  the Dubpods 6mm beading that is along the edge of connecting canopy into one side of the figure of eight and hook the other to the gutter rail. We recommend using a 6mm to 6mm drive away kit as it helps you to easily detach when you want to leave the dubpod standing.
You can then then clamp also with the gripper clamps
Drive Away and Leaving Up
You can detach the connector part and leave the Dubpod in position when you go out in your camper for the day. Simply add the two awning poles into the front eyelets on the connector and guy them down at the front.

You can also use Dubpod as a Stand alone tent by unzipping the awning connector sections and pitching as a Touareg tent.
I hope this helps but please feel free to ask as many questions as you need & also we are on 0115 966 3535 if you would like to talk it through.