Materials are attributes of (and stored in) the PLN file, not objects (unless defined specially in the object ... an advanced thing).
In your 3D script, the material is a parameter - "M0". So, when you place the tile in the new PLN (on the new machine), you need to open the object settings dialog and select the correct material. The object will have stored the material by a number which may not match the number assigned to the materials in the other PLN file. The desired material may in fact not be in the PLN file on the other machine, so the only easy way to get it there is to use Attribute Manager to transfer the material from the PLN file that has the desired material.
HTH,
Karl
AC 28 USA and earlier • macOS Sequoia 15.3, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB
One of the forum moderators