why have you changed the format ?
I was enjoying the challenge of accumulating the points to achieve the mastery. Although it took time by constantly forcing me to repeat answering questions, I felt it was sinking in. Now it is too easy to get past the mastery section by just completing one test after the lessons. I know you can go over old lessons but it loses the challenge element.
I don't like this either. (I just signed on and you must have made the change within the past 24 hours!) I much prefer practicing sentences that tell me what's going on grammatically, and then translating when I feel like it - and then going back and refreshing the grammatical knowledge. Most of all I don't like not being warned about the change!
I totally agree with both comments above and in particular with the lack of warning!
I also don't understand the tick marks on the "books". Does that mean you've done a lesson or that it's available to you? I can't remember which lessons I've done and it doesn't help when the system makes it hard to figure out. Not happy with the new look at all.