I think in this case, it can’t be done. The problem is that the pin numbers on the board appear to have changed since the first versions. If I compare the original CHIP.fzpz with the latest one, the breadboard view connector pin numbering is different (and the orientation of the board is rotated 180 degrees as well). Assuming the sketch you are trying to change uses the original part, the pin number change is going to screw up the routing (as the connector numbers have all changed). So I don’t think there is a way (even the " Delete Minus " isn’t going to work I don’t think because the traces will go to the wrong pins) to do the substitution. There look to be two choices: redo the entire sketch using the new part, or change the new part so the orientation and pin numbers are the same as the original part in the sketch, in which case at least the " Delete Minus " should work and there may be a way to manipulate the underlying files to do the substitution (although I haven’t made that work yet, but that may be because of the connector change which I hadn’t noticed).
Peter