See attached project. To use simply drag M&M's between holders and click "Multiply" button. Works fine.
But problems occur when you copy the Playfield containing the objects to another page in the book or even to the same page. While the Multiply function still works, if you look at the script it seems to be referring to the wrong object (I have a included visible scripts and a text field to demonstrate this).
The bigger problem occurs when you copy the playfield to another project. When you do this the "Mulitply" button breaks. To fix it you need to drag the "Set's" (the Holder with the multiplied M&M's) tile representing that object into the script and the references are fixed and all starts working. I included the instructions to re-create below and they are also in the project.
Project to demonstrate problem with Copy/Paste of objects
1) Select the Playfield below to see the Halo then hit the copy keys (ex: CMD-C)
2) Go to Page 2 and hit the paste keys (ex: CTRL-V)
3) You will notice the multiply script refers to "Set23" but it is actually for the new set (with a new name as reflected in the text) If you click on the Set on Pg2 and grab the tile representing the Set and drag it into the script, it will fix all the Object name (except the in the Script Title).
4) Now Move the M&M's between holders (or add them from the Maker button) and click multiply, it will work on both pages, but if you copy to a new project the multiply breaks. It can be fixed by simply dragging a tile representing the set from the Halo into the script. You only have to do this once and it seems to fix all the references.