@DaveBoyle - Keep us posted and like @mountainman says we'll all do our best to help you on your journey.
After rereading your original post, I have a couple other comments...
First, I don't think I have ever been successful with an LHT of 5. When I first got my unit I tried 5 a couple of times and ended up with flameouts. Situations seem very rare where that lowest feedrate can sustain a flame.
Also, try to minimize the variance between the 2 values. Part of your excessive smoke could be that your HHT drastically overshoots and then the LHT rate barely sustains the flame.
I pretty much run with theory 1 from the 1st link that mountainman listed. I initially set both values the same to determine the appropriate "pilot light" setting. Then add 5 to the HHT and let it be other than adjustments for significant changes in ambient conditions during the cook.