I haven't done any object meshing so really have no clue as to how to go about it. It would seem like cloning a Maxis bathtub from the game after Pets was installed and importing the meshes and textures into it would be the way to do it but I have no idea how to go about that.
Did you try getting in touch with the original creator to see if they had updated it?
Or you could try asking the modders at MTS2. There seem to be a lot more object creators over there than here.
I try all these and nothing.
I have this program but not update bathtubs....
Anyway, thanks for answering!