Yes windows 7 is supported
Cool…
Would this be a good drive to use?
WD 4TB Black My Passport Portable External Hard Drive - USB 3.0 - WDBYFT0040BBK-WESN https://www.amazon.com/dp/B01LQQH86A/ref=cm_sw_r_cp_tai_ANQsAb8195ARD
Also, is there a step-by-step guide or tutorial on what it takes to get it set up?
Yea that drive should be fine.
There’s honestly not much to it. Plug everything in and install the app and DVR. It should guide you through the setup, which includes:
- scanning for channels from the app
- selecting your drive as storage in the DVR
- entering your zipcode and picking Comcast
Probably the most annoying part is getting the CableCARD activated by plugging it in and then calling Comcast and telling them the details found on https://my.hdhomerun.com under the CableCARD menu.
Sounds easy enough 
I assume that getting HDHR Prime up and running with te Channels App and ATV should be my first priority?
Thanks for answering all of my questions! I’m sure that I will have more 