The water runs and will not shut off.

Here's what happened: when you press on the flush lever, it pushes down on the cartridge, which starts the flush. However, in your tank, the lever cannot touch the cartridge.

1. Loosen the setscrew (this may be located on the side or on the top of the actuator).
2. Turn the actuator counter-clockwise approximately half a rotation. The actuator should raise.
3. Flush the toilet.
4. Does it flush properly?