They also have blank acrylic Plexiglas plates, and you can make up the bit hole how ever you want it that way. They stock it in 1/4" and 3/8" thick, and really, the 3/8" is the way to go, especially if you want to use any sort of insert, for minimum warpage, or you have a heavy router.
You can buy more of this acrylic, and use a radius-type circle cutter, or trepanning tool, to cut out and countersink a large hole for the bit, and make your own inserts. General makes the tool, along with others, and can be purchased pretty cheap.
You can make the cutout using simple flat boards with double-sided tape laid out in an outline of the plate, and using a top-bearing flush trim-pattern bit to make the cuts. Simply place the plate where you want it to go by using a small amount of double-sided tape so it wont scoot around. Place the boards around the perimeter using tape. Next, pull up the plate from the middle, and place the plate on top of one of the boards, then the router on top of that. Then, bring the bit down until it tips the table, and set it's depth of cut there. Remove the plate from the top of the board that you used for a height reference, put the router base on top of a board, and plunge in the bit to the stop, then trace the bearing around the boards. Last, cut out the center piece for the router to go through with a saber saw. The routed ledge should be exactly the right depth to match the plate thickness, since it was used as a height reference. I always made the ledge using a 3/4" bit, so I got a 3/4" ledge all around. If your off a little, its better to be too deep, that not deep enough, to the ledge. If your too deep, you can drill and tap the 3/8" acrylic on each corner, and use some small leveling screws.
The MCLS pattern is simply the same thing as adding the boards around the plate, its just a pattern.