Hi, I started this book in January (I think it was?). GREAT book. It took longer than 7 days, but it did work. You just have to be consistent.
The rain --- you go out, and you stand in it, no longer how long it takes. You have to teach them that it doesn't matter if it rains, they have to do their business. And by you standing there with them, you're showing them that if you can do it, so can they. You're setting the example. Cannot tell you how many times I've had to stand through torrential rainstorms just to get the potty.....they finally learned.
Best of luck!!