Hi Lewis - sorry the v4 beta is not too close yet there is still a lot of work to do before it will be ready.

If you're still having problems you might try exporting some pieces to separate 3DM files and then starting a new instance of MoI and only loading one of those pieces at a time (with the coarser display mesh settings as in the previous link, don't forget to do that as well) and that will also reduce memory load only having some portion of your model even loaded at any one time.

- Michael

I've managed to do export in several pieces with display adjustments and a bit lower settings than i initially planed (still look decent on render) you mentioned in that topic so all good export vise (on this project) :).