I just uploaded version 0.8. I've updated the graphics for the pieces that are meant to fit together. I've added an indicator on the edges of the rolling block when on of the pieces is present on the side. I'm not sure if this is working as well as I'd like - I may need to just make the piece visible through the block when the block is selected. I've updated the connector piece a bit. I've also added a new piece...the disconnector. It looks a little rough right now and needs a cosmetic update. It is functional, however. When you touch a block to a disconnector of the same color, all of the connectors on that block will be deactivated and the blocks will separate again. The disconnector code splits the blocks into multiple blocks in mid-movement and copies the rotation data. It's complicated and I made it that way so I could support an edge case where a block could disconnect and then only the pieces that collided into other blocks would bounce back. If I had it to do over again there's a good chance I would skip that edge case since it made several foundational systems quite a bit more complex. The Undo button currently doesn't work properly after you've hit a disconnector. Should be fixed in next update.