The following bug is tested to be happening for the blocks: all dirt blocks (except 6-6 and 6-7, as well as dirt blocks that use a dirt hill [terraform])
When creating a custom block from a dirt block, it is not possible to use it on dirt surface, since you can only create that block with a grass surface. When placing the custom block on dirt surface, it is becoming uncollidable!

The following bug is tested to be happening for the blocks: 6-1-11, 6-1-12
There is no existing geometry when trying to create a block from 6-1-11 and 6-1-12, just the default cube
