DarwinBabe- if you want to substitute something in a recipe, try to make it like for like. Lentils are not a substitute for cauliflower because they much higher in calories. At the end of the day if you stick to 800 calories you should lose weight, and if you do go up, consider water weight.
I also think you are out of line in the way you’ve addressed Penny- we’re pretty friendly and caring in the forum and what you’ve said were neither. Penny’s question was perfectly legitimate given your user name so if you don’t want to risk your anonymity I’d suggest choosing a more anonymous user name. Anyway, good luck.