Passat 2005 Running On Used Soy Oil And B100

I've just passed the 1000 mile mark on SVO. Here's a day in the life with my Passat. In the mornings I start the car on BioDiesel. This comes from my 5 gallon doughnut tank that sits in my trunk inside the spare wheel. I have a red button switch on the front dash board near the radio. When the light is red I know I'm on the BioDiesel tank. I start driving. By the time I get to the freeway on ramp, in about 2 to 4 minutes, the engine is hot. When I see the temp gauge at 190 I flip the switch, I probably could do it sooner since I have the vegtherm device but I wait anyway, the switch light turns off, and the 6 port switch under the hood does its magic and switches the hoses to start pulling from the main tank and the engine starts eating svo. The vegtherm also does its magic and heats the oil before it gets to the injectors. Right before I get to my destination, if I know I'll be there more than 2 hours, I'll flip the switch again and purge the svo out of the engine.
The Switch  This way, when I start the engine cold it will start on biodiesel and not svo. If its warm outside, 70 degrees or so more and I'm stopping for less than 2 hours I won't purge. I'll start the car on svo. I've noticed that if I miss judge the temp out side or wait longer than 2 hours than the car might not start on the first key turn but on the second turn it does. If that happens then I sometimes notice a cloud of white mist coming out of my tail pipe on start up due to the incomplete combustion from the cold start. This could also be due to some water in the svo. I'm still investigating. Other things I've learned The 5 gallon tank doesn’t have an indicator as to when it’s empty. However, I found a trick to know when I have to refill it. In the mornings, when the car doesn't start right away on the first key turn it's ready to fill. Why you say? Well it's because of the svo purge. Each time you purge, a little svo gets in the BioDiesel tank. As the concentration of svo builds up in the bd tank over time it starts to become noticeable because the car doesn't start on the first key turn as it always does when it's just biodiesel. This happened to me the other day. I looked in the bd tank and sure enough it was almost empty. After I filled it, the car started right away on the first key turn.