The cheesy pasta is great - if you like cheese, you'll love it. I'm assuming of course that it's the same sauce as the previous one they had - I'm receiving my free sample today sometime so I'll comment then.
The feelings of run down / slight ache / decreased energy / brain "fog" ... well.. it's normal on a VLCD. Muscle wasteage will happen regardless, but nowhere near as much as you think. My muscles only noticeably started depleting when I went past the BMI 25 mark previously (so with much less fat storage to choose from). So I wouldn't worry about it too much.
But if you do want to increase protein intake - you could have a boiled egg, or make a porridge pack with an egg white into a pancake. The egg-white itself is the least calorific part of the egg (17-20 cal?) and it's the protein rich segment.
Do what you feel you need to do in regard to number of packs, the weight will come off regardless

I can't comment on how fast/how slow if you are having an extra one. There is research to say that people lose similar amounts of weight when they eat 650 cal/day or
800-1000 cal/day (which an extra pack+veg gives you)... play it by ear.
You're doing fab, keep the diary up - it helps keep the monotony and boredom of this diet at bay.. at least for quite a few of us anyway.
x