Hi Psygorn,

re:
> @Michael, what is the limit size of MOI3D? I mean the .3dm file is around 300 MB! (I haven't
> reached these sizes before! and MOI starts to getting slow! when it does it's calculations it's as
> if it will take for ages!"

There is not really a single hard size limit, it depends on a lot of factors like what hardware you're on and the particular type of geometry you are using (like lots of little fillets).

If things are bogging down in 3D view navigation you can try going to Options > View and set Mesh angle to 25 and uncheck "Add detail to inflections". That will make for a rougher looking display but faster.

- Michael