The Stack System Putting - Indoor users?

[Rearviewmirror]

With winter starting to ramp up, I was wondering if anyone has been using The Stack's putting system for indoor practice? I have a 14x3ft Birdbieball mat and hoping to get some good putting drills in over the winter months as well as on course putting green when I can.

[Spinedoc2304]

I use it during every range session. I’ve dropped approx. 5-6 putts/round. 
The app has you put various lengths of breaking putts both uphill and downhill ( and flat). As an example, it’ll say “ 15 feet, downhill, left to right “.

So unless you can recreate these conditions indoors, the resulting stats it gives you will be meaningless 

[Retsof2021]

I’ve used it twice so far and I must say the insights are incredible. Not sure I fully understand how to categorize my putts though. For me, that piece seems a bit complicated. Below are the options. I usually forget that hitting it too soft on line is technically a “misread” as per the putting quiz and not “slow”. Anyone have any “ahas” for how to make sure you categorize it correctly?