The offset option currently moves the mesh in mesh units.

For example, the units of rabbit.ply appear to be meters, which would make the original mesh about 7 cm tall. So if you enter an offset of 1.0, the original mesh moves 1m off screen, outside of the maximum build area.

This is fine if you actually select units=meters, and scale=1, because then you can offset by .01 and move the model 1 cm, which is perfectly reasonable.

However, if you didn't know that the units of the original mesh where in meters, you would likely use some units you know, and then use the "max size option". If you were to choose 9 studs, for example, the scaling factor is 2546. Now if you offset it by 1 unit, your model ends up 2546 studs off screen.

Instead, it would make sense for the offset occur after scaling, in the selected units. Labeling the offset units would also help.

Alternatively, if you are only dealing with one object, there is no need to ever offset the model by more than 1 stud in any direction, because the results of offset=n studs and offset=n + 2 studs are identical. So you could replace the entry box with a slider that goes from -1 to 1 stud. (or 0 to 2 studs)