The Support Blocker is NOT in the bench.
K_W asked about this in an earlier post in this topic. And several people offered suggestions on how to compensate for the missing support blocker. Why they can't bend the rule just this once and allow the import of one object, to compensate for an oversight in the bench development... Go figure.
Some bits are used for inverted tracks and others are used for standard track. The supports never work out to rest perfectly on a continuous flat surface. You either have to create tall stacks of concrete pilings for anchors to the ground, OR lift the tiles to be taller, or lower them down into a sort of shallow hole to compensate for the height that you choose to "attatch" the support to the tracks.
You'll have to use Zero Clearance to get the pieces to "attatch" to the track, and there's no garantee that the alignment is going to work out anyway. Not to mention how objects tend to disappear when the tile beneath them is adjusted. Talk about exasperating.
There are identical looking pieces that can be placed in like 21 or more combined locations on a single tile. So it's a tough nut to crack and to get every piece located properly, especially on a tall lift hill or any elevated section that's really high in the air. Because from one angle, it'll look like it works, but rotate the park and you'll discover you're off by a couple tiles, and you'll end up with a chunk of support floating in mid-air somewhere.
So having until Feb. 28th. is a blessing if you want to get into B&M supports. But it's kind of unwise to try and use them in a compo, IF you never used them before. But if you're up to the challenge, and if you don't mind going insane, give it a try.