Your "How To" install video shows the flooring butted up to existing baseboards. Is that the standard/required practice? I intend to install baseboards after the flooring is installed, with the baseboard resting on the flooring. Is that okay? Also, can you caulk the crevice between the baseboard and flooring for a liquid-tight joint?

In a real world installation, you would install the planks underneath the baseboards to allow for the proper expansion/contraction space. Base boards must not be fixed in a way which restricts the movement of the floor (ex. nail through the floor). If you would like to caulk the visible gap between the baseboard and the flooring, you certainly can.