This seventh puzzle is the first of the difficult ones, so get your thinking head on. Don't forget you can use the "Undo" button to go back if you find you've gone wrong.
As before, use your mouse to left-click to select numbers you're sure of, and right-click for numbers you think are possibles. Use the "Float Window" button to popup a new window which you can make bigger or smaller as you want.
According to Sudoku Sensei, this puzzle is coded as
N2x03-059 which means three level 2 rules are needed to solve it, and it starts with 59
empty squares. The extra level 2 rules bump the complexity up to difficult.