I'm doing the tutorial and having never really understood regex, i just fill in 'A' everytime, and i pass all the tests. Not learning anything though.
If you click Validate it'll shake and turn red, though you can skip ahead all you want, you want it to turn green and add a checkmark next to the title.
I guess all I showed was that if you don't want to learn, you're not gonna learn.
I'm no regex beginner but this overall presentation is pretty confusing.
If you find the interface confusing, start with the tutorial levels which begin with a single character solution and progress to larger solutions. Each cell is clearly meant to be one character in a string, with the row/column being the entire string.