Methods and apparatus for applying coating to products such as medicaments are disclosed. The present invention provides apparatus and methods for controlling the loading and feeding of tablets onto carrier plates for transfer to various processing stations of the coating system. A novel plate indexing apparatus includes a box cam follower device mounted to an engagement bar for incrementally advancing the plates in a precisely controlled manner. A second complementary shaped engagement bar provides a locking mechanism to ensure the plates are always under positive control. In one embodiment the plate indexing apparatus also controls the feeding of the tablets. An alternative embodiment includes a vacuum pick-up system for feeding tablets onto the carrier plates as the plates are incrementally advanced.