Hi Leonard, the processing that does the conversion to 2D and causes the growth spurt is happening inside of VectorWorks, is that correct?

If so then I don't know of anything you could do on the MoI side to prevent that, maybe there are some settings for the VectorWorks conversion mechanism that you could loosen to prevent excessively dense geometry from being created by VectorWorks. MoI itself is not able to influence settings that are specific to VectorWorks like that though.

You probably need to investigate what in particular is taking up most of the file size - is it that there is a tremendous number of curves? Things fragmented into little bitty pieces? Each curve having zillions of points in it? Or ? ... Once you know why it is so large that may suggest some course of action.

- Michael