Hey
don't worry too much about the ketostix changing colour - mine didn't change colour for 6 days after i started!!, but i'd still lost 8lbs. sometimes the sticks are faulty, sometimes (because you're drinking so much water), there arent enough ketones to detect.
as long as you're following the diet correctly, you'll be in ketosis.
i have had a MIM a day and i'm still losing. i just have to be careful with cheese as i sometimes have too much without noticing.
also, you asked earlier about soft drinks? i have been drinking diet coke caffeine free. there's no sugar, and the book said to avoid caffeine, so ticks all the boxes.
also you can have Oasis Light, and Vimto Diet (both are 0.something sugar)...these are the only drinks i've looked up and drink.
hope this has been useful - you seem to have it sussed so far!! xx