I found an annoying detail regarding the height of the grid snapping.
The issue arises only in connection with the ground.

The tunnel blocks seem to snap in a lower height than all other blocks. But this is actually not the case. They all have the same grid snap level. The reason the tunnel entrance and all the other cliff roads are a bit higher is the connection with the ground.
The lowest step of the block grid on the ground is actually smaller than all other ones.
If you watch closely, you will detect the smaller gap between the two lowest tunnel pieces.

(the black bars I added are identical in size)
The one in the ground is slightly lifted to fit the level of the ground. This lifting happens with all cliff blocks as well, so that they are higher than the regular scroll level, when placed on the ground.
You can even see this ingame, when you select a bend tunnelpiece and starting from somewhere in mid air carefully scroll the piece down to the ground. At first you will see that the tunnel piece is slightly under ground, but once you move the mouse by the tiniest bit, it will attach to the surface on the ground and thus jump a little step higher, which is exactly what happens with all other objects placed on the ground as well.
I don't know what the easiest way to fix it is, but maybe it is possible to change the grid snapping of all these objects, so that they are a bit higher and fit to the road levels (and the ground level).
I hope you can somehow fix this inconsistency because it is annoying to place tunnel blocks in the correct height (I actually don't even know how to achieve this

)
And thanks for those amazing blocks. They are beautiful
