This mod changes many full nodes, slabs, and stairs to have studs on top to look like interlocking bricks. I have tested it with Minetest Game and Mineclonia, so it should work with MineClone2 or MineClone5.
Many naturally generated nodes do not have studs, to avoid a Minetest rendering performance problem. You can read more about that here: https://forum.minetest.net/viewtopic.php?f=7&t=28068&p=409857
well, it's not a secret that voxel games are looking familiar to LEGO, and not a first mod/resourcepack/etc that makes blocks/nodes look like LEGO, but still it's the first minetest mod that does something like that!
TIP: if you want to place node with studs on top of other node with studs, then you need to point accurately on center of that node (to avoid placing on studs). if you will try to place node while pointing on studs, it will just place it 2 nodes above (so it will be like node-air-node instead of node-node) or in place where you're standing.