I have been contemplating how they would actually do cutting and carving, and the sad reality is that if they stick with the cloud aspect of sharing, they will not give this to us. It is a technical limitation in the fact that pieces are pieces. Welded pieces are not new pieces, and cannot be. Instead, they are a cluster of instructions more complex for assembly of many pieces. Given this reality, it would be hard for the game to store precisely how a piece should be stored after being sliced or carved. That becomes a new piece which would have to sit on your hard drive, and would be really hard to find a way to make work with a cloud storage scheme. It might be possible for them to do something like this, but I highly doubt they will, due to the limitations described herein.