I am not familiar with the belt you are talking about. But I will insert some tried and true advice here...
If you have a gut that hangs over... you have excess body fat or lose skin from all of your pervious weight loss. If it is excess skin... then surgery may be your only hope. I AM NOT ADVOCATING SURGERY. But for excess skin from extreme weight loss surgery is typically the only solution. If you are young and your skin still has elasticity in it... it could bounce back and tighten a bit. Not sure of your situation.
However if it is simply extra fat... then you need to reduce overall body fat. You can do 1000 crunches a day and that will do nothing but work your stomach muscles. It will not touch the fat there.
To reduce overall body fat... you must do these 5 things congruently...
1) Eat 5-6 small meals throughout the day. Each meal should be 2-3 hours apart. Each meal should contain one protein and one carb. The first meal should be eaten within an hour after waking.
2) Drink lots of water
3) Rest properly. This means taking at least 24-48 hours between strength training the same muscles, and it also means getting at least 7-8 hours of sleep per night. Lastly, it means taking 1-2 days off from exercising per week.
4) Cardio. This should be done at different intensity levels and different session lengths. Consider doing a low intensity/long session, a high intensity/short session and a few medium intensity/medium length sessions.
5) Strength Training. Strength train each muscle 1-3 times per week. You should lift a proper weight and perform the proper amount of sets/reps for your strength training method.
All of the above things combined will result in fat loss. The belt you are referring too... does it simply warm you up so you sweat more? That is the impression I got from your post. If so... send it back and get your money back. You'd be better off investing in my ebook
To get rid of dead skin... use a loofah or washcloth to bathe yourself. To get rid of cellulite... sorry the only way to do this is to reduce overall body fat. Follow the 5 tips from above.
Glad you do not believe in the hype of losing an inch per day and all that BS. Because it doesn't work. I've seen belts like this come and go so many times before. To get a flat stomach... reduce overall body fat. Good luck!!