My first winterization

If you use a biological tank additive such as TankTechs Rx, Septa-Flush, Bio-Clean, Happy Camper, RV Digest-It, or something similar then leaving stuff in the black tank should be no problem. These assist in liquefying the solids so that they don't mat on the bottom.

I actually did all of that. So hopefully i should be good. The only thing i have a concern about was, the line from the fresh tank, to the pump. I did add a little AF to the fresh tank, just because, but i didnt cycle it thru the line. I hope thats ok. I had pink stuff coming out of every tap faucet, and both shower heads, so i feel all those lines are set. 

I watched the KY Moose Youtube video - blowing out the lines and NOT using the RV antifreeze siphon.

Sorry about that, my 177 is an older style (2011 model) and am not sure if all but at least some of the newer models only have 2 valves to bypass the hot water tank.  I have never used my city water connection (we either dry camp or bring our own well water with us) so have always used the pigtail from the 3 way valve located under the sink, I believe that is standard on all pods, as far as its location. 

As far as your black and gray water tanks, I have never blown out either, just drain them out in fall before going into hibernation mode.  Also I have never added antifreeze to any of my 3 tanks, if they are drained and maybe have a few gallons in them, that leaves plenty of space for expansion in a 30 gallon tank as it freezes.  This will be the 7th winter our pod has gone through, no issues ever with freezing lines, pipes, or tank ruptures.  This morning 15 degrees, ahhhh, winter is just beginning.

Close your 3 valves (each goes 1/4 turn) to put it into bypass mode.  You are correct, NO antifreeze in the hot water heater.  Find your 'pigtail' under your sink where you will see a 3-way valve.  After putting your 3 valves above your hot water tank into bypass, come back under your sink and locate the 3-way valve and turn it 1/4 turn.  Find the pigtail (about 12-14 inches long) and put the end of that into your 1 gallon pink antifreeze.  Turn on your water pump and open each hot and cold tap until you have pink coming out of the faucet.  Do this 1 at a time, not all at once.  Finish by turning on your water closet (toilet) until pink comes out of that as well.  Walla, you are done.  No need to put antifreeze in the fresh water tank.  I am sure you notice there is probably a few gallons in the bottom that you can't get out BUT there is plenty of room for expansion so no worries.  Yes, put some of the pink down your shower and kitchen drains.  No need to put down the toilet but DO put some on top of the valve cover to keep the seal lubricated during the hibernation mode.

For the past 6 years I have simply blown out the lines using compressed air, takes about 1 minute once I am hooked up to the pigtail you use to suck in the antifreeze.  Once that is done I use 1 pint of antifreeze for the 2 sink and 1 shower trap and also use a few ounces to put on top of the toilet seal.