If I have a matrix of the same thing, repeated in X and Y, I would be able to fit them all onto the remaining wood/acrylic, except that the layout is too tall / too wide.
If I could specify this section, then that section I could fit them onto the remaining wood (for example) but a single pass layout wouldn’t fit the geometry of the wood I have.
It’s easy to do, if the design is simple (just select the parts you don’t want, set to a non-cut layer, and you’re done). If you’ve got 5 or 6 layers already in each node in the matrix of things though, it’s a bit more of a pain…