I know all about the temptation to eat. This is day 21 for me and I was REALLY HUNGRY until day 16, now I am rarely hungry. But, here is what I know to be true: the fast gives your digestive system a break, and having nothing to digest for a while actually helps control your appetite. Every time we give in, even for a little bite of something, we get our digestive working again, and that stimulates our appetite.
On my first two days of the fast, I think I drank 15 glasses of the MC! I was so, so hungry. Then, I reduced it to about 10, and now I have to really try to remember to have at least 6!
I would really urge you to just have more of the Master-Cleanse every single time you get hungry. Eventually, I think your hunger will become manageable.
Regarding the SWF, it can be a challenge. Here's what I do: I have an hour commute to work, so I only have water when I wake up, and then heat up the water before I add the salt, and then take it with me to drink during the second half of my drive. Once I get to work, my office is near a bathroom, so I just make a lot of trips. And it's ok. Some days I hardly go at all, and others, it's like every 10 minutes and I don't understand that, but it's outside of my control. About an hour or so after I drink the SWF, I have my first Master-Cleanse of the day.
It has worked out fine for me. The first few days were the hardest, so remember that and hang in there! It's really, really worth it.