Current interaction is limited to the base of the vending machine. Though the bounding box extends to the top block, the player cannot interact with the top block.

You can even place a block in the top block.

Yep. Should be address with the same fix. Essentially I am adding a gag block to the top part of the vending machine. It is essentially becoming a multiblock structure when placed into the world.

Fixed v0.4.2.7