Step 10: Cut around door casings.
Instead of cutting planks to fit around door casings, use a jamb saw to cut the door casings. Cut the door casings 1/16-inch above the height of the laminate flooring, allowing room to slide the planks under the casing.

Step 11: Install the last row.
You will likely need to trim the last piece according to your calculations from Step 4. The last row may be awkward to install because there should be only ¼-inch between the last row and the wall. Slip the planks into position at an angle, and gently push into place with a pry bar.